Alleviation of Ultraviolet B-Induced Photodamage by Coffea arabica Extract in Human Skin Fibroblasts and Hairless Mouse Skin

Chlorogenic acid attenuates deoxynivalenol-induced apoptosis and pyroptosis in human keratinocytes via activating Nrf2/HO-1 and inhibiting MAPK/NF-κB/NLRP3 pathways

Deoxynivalenol (DON) is a common mycotoxic contaminant, frequently found in food and feed, causing a severe threat to human and animal health. Because of the widespread contamination of DON, humans involved in agricultural practices may be directly exposed to DON through the skin route. Chlorogenic acid (CGA) is a phenolic acid, which has anti-inflammatory and antioxidant properties. However, it is still unclear whether CGA can protect against DON-induced skin damage. Here, the effect of CGA on mitigating damage to human keratinocytes (HaCaT) triggered by DON, as well as its underlying mechanisms were investigated. Results demonstrated that DON exposure significantly decreased cell viability, and induced excessive mitochondrial reactive oxygen species (mtROS) generation, mitochondrial damage, oxidative stress, cell apoptosis and pyroptosis. However, CGA pretreatment for 2 h significantly increased cell viability and reversed DON-induced oxidative stress by improving antioxidant enzyme activities such as superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), reducing mtROS generation and enhancing mitochondrial function through activating Nrf2/HO-1 pathway. Moreover, CGA significantly increased the Bcl-2 protein expression, decreased the protein expressions of Bax and cleaved Caspase-3, and suppressed the phosphorylated of ERK, JNK, NF-κB. Further experiments revealed that CGA could also inhibit the pyroptosis-related protein expressions including NLRP3, cleaved Caspase-1, GSDMD-N, cleaved IL-1β and IL-18. In conclusion, our results suggest that CGA could attenuate DON-induced oxidative stress, inflammation, and apoptosis by activating the Nrf2/HO-1 pathway and inhibiting MAPK/NF-κB/NLRP3 pathway. CGA might be a novel promising therapeutic agent for alleviating the dermal damage triggered by DON.

Coffea arabica Extract Attenuates Atopic Dermatitis-like Skin Lesions by Regulating NLRP3 Inflammasome Expression and Skin Barrier Functions

Atopic dermatitis (AD) is a common skin disease worldwide. The major causes of AD are skin barrier defects, immune dysfunction, and oxidative stress. In this study, we investigated the anti-oxidation and anti-inflammation effects of Coffea arabica extract (CAE) and its regulation of the skin barrier and immune functions in AD. In vitro experiments revealed that CAE decreased the reactive oxygen species levels and inhibited the translocation of nuclear factor-κB (NF-κB), further reducing the secretion of interleukin (IL)-1β and IL-6 induced by interferon-γ (IFN-γ)/tumor necrosis factor-α (TNF-α). Moreover, CAE decreased IFN-γ/TNF-α-induced NLR family pyrin domain-containing 3 (NLRP3), caspase-1, high-mobility group box 1 (HMGB1), and receptor for advanced glycation end products (RAGE) expression levels. It also restored the protein levels of skin barrier function-related markers including filaggrin and claudin-1. In vivo experiments revealed that CAE not only reduced the redness of the backs of mice caused by 2,4-dinitrochlorobenzene (DNCB) but also reduced the levels of pro-inflammatory factors in their skin. CAE also reduced transepidermal water loss (TEWL) and immune cell infiltration in DNCB-treated mice. Overall, CAE exerted anti-oxidation and anti-inflammation effects and ameliorated skin barrier dysfunction, suggesting its potential as an active ingredient for AD treatment.

Prospects of Coffee Leaf against SARS-CoV-2 Infection

In the current climate, many countries are in dire need of effective preventive methods to curb the Severe Acute Respiratory Syndrome Coronavirus Type 2 (SARS-CoV-2) pandemic. The purpose of this research is to screen and explore natural plant extracts that have the potential to against SARS-CoV-2 and provide alternative options for SARS-CoV-2 prevention and hand sanitizer or spray-like disinfectants. We first used Spike-ACE2 ELISA and TMPRSS2 fluorescence resonance energy transfer (FRET) assays to screen extracts from agricultural by-products from Taiwan with the potential to impede SARS-CoV-2 infection. Next, the SARS-CoV-2 pseudo-particles (Vpp) infection assay was tested to validate the effectiveness. We identified an extract from coffee leaf (Coffea Arabica), a natural plant that effectively inhibited wild-type SARS-CoV-2, and five Variants of Concern (Alpha, Beta, Gamma, Delta, and Omicron strain) from entering host cells. In an attempt to apply coffee leaf extract for hand sanitizer or spray-like disinfectants, we designed a skin-like gelatin membrane experiment. We showed that the high concentration of coffee leaf extract on the skin surface could block SARS-CoV-2 into cells more potently than 75% Ethanol, a standard disinfectant to inactivate SARS-CoV-2. Finally, LC-HRMS analysis was used to identify compounds such as caffeine, chlorogenic acid (CGA), quinic acid, and mangiferin that are associated with an anti-SARS-CoV-2 activity. Our results demonstrated that coffee leaf extract, an agricultural by-product effectively inhibits SARS-CoV-2 Vpp infection through an ACE2-dependent mechanism and may be utilized to develop products against SARS-CoV-2 infection.

Precise Diabetic Wound Therapy: PLS Nanospheres Eliminate Senescent Cells via DPP4 Targeting and PARP1 Activation

Diabetic ulcers, a difficult problem faced by clinicians, are strongly associated with an increase in cellular senescence. Few empirical studies have focused on exploring a targeted strategy to cure diabetic wounds by eliminating senescent fibroblasts (SFs) and reducing side effects. In this study, poly-l-lysine/sodium alginate (PLS) is modified with talabostat (PT100) and encapsulates a PARP1 plasmid (PARP1@PLS-PT100) for delivery to target the dipeptidyl peptidase 4 (DPP4) receptor and eliminate SFs. PARP1@PLS-PT100 releases encapsulated plasmids, displaying high selectivity for SFs over normal fibroblasts by targeting the DPP4 receptor, decreasing senescence-associated secretory phenotypes (SASPs), and stimulating the secretion of anti-inflammatory factors. Furthermore, the increased apoptosis of SFs and the disappearance of cellular senescence alleviates SASPs, accelerates re-epithelialization and collagen deposition, and significantly induces macrophage M2 polarization, which mediates tissue repair and the inflammatory response. This innovative strategy has revealed the previously undefined role of PARP1@PLS-PT100 in promoting diabetic wound healing, suggesting its therapeutic potential in refractory wound repair.

Comparison of Single and Combined Use of Ergothioneine, Ferulic Acid, and Glutathione as Antioxidants for the Prevention of Ultraviolet B Radiation-Induced Photoaging Damage in Human Skin Fibroblasts

Ultraviolet B (UVB) irradiation can cause human skin damage or skin aging and wrinkle formation through photochemical reactions. Antioxidative substances may ameliorate UV damage. In this study, the anti-photoaging activity of three antioxidants—ergothioneine, ferulic acid, and glutathione—was investigated after UVB irradiation of Hs68 human skin fibroblast cells. The cells treated with these three antioxidants appeared similar to unirradiated control cells. UVB irradiation decreased cell viability by 26% compared to that of unirradiated control cells. However, the addition of either single or combined antioxidants enhanced cell viability after UVB irradiation. These three antioxidants can inhibit the production of reactive oxygen species (ROS) induced by the UVB irradiation of the Hs68 cells. Ergothioneine showed a greater inhibitory effect on matrix metalloproteinase-1 (MMP-1) performance than the other two antioxidants. IL-1 alpha was not detected in the Hs68 cells after exposure to a radiation dose of 150 mJ/cm2. Ergothioneine showed better restoration of type 1 procollagen than either ferulic acid or glutathione. Based on these results, the addition of two antioxidants was expected to restore type Ι procollagen production. In summary, these results demonstrate that the three tested antioxidants protect the skin against UVB-induced damage. The single and combined use of ergothioneine, ferulic acid, and glutathione has the potential for development as anti-photoaging materials in cosmetic applications.

Melanogenesis effects of rice protein hydrolysate and its characteristic peptides Leu-Leu-Lys, Leu-Pro-Lys, and pyroGlu-Lys on UVB-induced human epidermal melanocyte cells

This study assessed the melanogenesis effects of rice protein hydrolysate (RPH) and explored the underlying molecular mechanism of its characteristic peptides. In this investigation, human epidermal melanocyte (PIG1) cells were used to establish a UVB-induced model to evaluate the effect of RPH on melanin content, tyrosinase activity, and reactive oxygen species (ROS) levels. High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed to identify the peptide composition (2-4 amino acids) in RPH. Enzymatic hydrolysis was employed to screen the characteristic peptides Leu-Leu-Lys (LLK), Leu-Pro-Lys (LPK), and pyroGlu-Lys (pEK), while their effect on the molecular mechanism involved in the melanin synthesis process was further explored using quantitative real-time polymerase chain reaction (PCR) and western blotting. The results indicated that RPH reduced the melanin content, tyrosinase activity, and ROS production in PIG1 cells. The selected peptides LLK, LPK, and pEK from RPH reduced the expression of tyrosinase-related protein 1 (TRP-1) and tyrosinase-related protein 2 (TRP-2) and affected melanin synthesis by regulating the JNK/β-Trcp/NFκB-p65/MITF signaling pathway at the mRNA and protein levels. This study shows that RPH plays a vital role in the melanogenesis process, therefore, providing a theoretical basis for the use of RPH as a novel additive product.

Antioxidant Properties of Plant-Derived Phenolic Compounds and Their Effect on Skin Fibroblast Cells

Plants are rich sources of a diverse range of chemicals, many of which have significant metabolic activity. One large group of secondary compounds are the phenolics, which act as inter alia potent reactive oxygen scavengers in cells, including fibroblasts. These common dermis residue cells play a crucial role in the production of extracellular matrix components, such as collagen, and maintaining the integrity of connective tissue. Chronic wounds or skin exposure to UV-irradiation disrupt fibroblast function by the generation of reactive oxygen species, which may damage cell components and modify various signaling pathways. The resulting imbalance may be reversed by the antioxidant activity of plant-derived phenolic compounds. This paper reviews the current state of knowledge on the impact of phenolics on fibroblast functionality under oxidative stress conditions. It examines a range of compounds in extracts from various species, as well as single specific plant-derived compounds. Phenolics are a good candidate for eliminating the causes of skin damage including wounds and aging and acting as skin care agents.

The Anti-Melanogenesis Effect of 3,4-Dihydroxybenzalacetone through Downregulation of Melanosome Maturation and Transportation in B16F10 and Human Epidermal Melanocytes

The biosynthesis pathway of melanin is a series of oxidative reactions that are catalyzed by melanin-related proteins, including tyrosinase (TYR), tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2). Reagents or materials with antioxidative or free radical-scavenging activities may be candidates for anti-melanogenesis. 3,4-Dihydroxybenzalacetone (DBL) is a polyphenol isolated from fungi, such as Phellinus obliguus (Persoon) Pilat and P. linteus. In this study, we investigated the effects and mechanisms of DBL on antioxidation and melanogenesis in murine melanoma cells (B16F10) and human epidermal melanocytes (HEMs). The results indicated that DBL scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals, and exhibited potent reducing power, indicating that it displays strong antioxidative activity. DBL also inhibited the expression of TYR, TRP-1, TRP-2, and microphthalmia-related transcription factor (MITF) in both the cells. In addition, DBL inhibited hyperpigmentation in B16F10 and HEMs by regulating the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA), v-akt murine thymoma viral oncogene homolog (AKT)/glycogen synthase kinase 3 beta (GSK3β), and mitogen-activated protein kinase kinase (MEK)/extracellular regulated protein kinase (ERK) signaling pathways. DBL not only shortened dendritic melanocytes but also inhibited premelanosome protein 17 (PMEL17) expression, slowing down the maturation of melanosome transportation. These results indicated that DBL promotes anti-melanogenesis by inhibiting the transportation of melanosomes. Therefore, DBL is a potent antioxidant and depigmenting agent that may be used in whitening cosmetics.

Photoprotective effect of Astragalus membranaceus polysaccharide on UVA-induced damage in HaCaT cells

Background

The skin provides a predominant barrier against chemical, physical and microbial incursion. The intemperate exposure to ultraviolet A (UVA) radiation can cause excessive cellular oxidative stress, leading to skin damage, proteins damage and mitochondrial dysfunction. There is sufficient evidences supporting the proposal that mitochondria is highly implicated in skin photo-damage.

Methods

In the present study, a polysaccharide isolated from Astragalus membranaceus was further purified to be an α-glucan, which was further investigated its beneficial influence on UVA-induced photo-damage in HaCaT cells.

Results

Our results showed that the purified Astragalus membranaceus polysaccharide (AP) can protect HaCaT cells from UVA-induced photo-damage through reducing UVA-induced intracellular ROS production and mitochondrial membrane potential, thereby altering ATP content. It was found that the UVA induced damage in HaCaT cells could be effectively restored by co-treatment with AP.

Conclusions

AP exhibited promising potential for advanced application as multifunctional skin care products and drugs.

Sweet Cherry Byproducts Processed by Green Extraction Techniques as a Source of Bioactive Compounds with Antiaging Properties

In the cosmetic industry, there is a continuous demand for new and innovative ingredients for product development. In the context of continual renovation, both cosmetic companies and customers are particularly interested in compounds derived from natural sources due to their multiple benefits. In this study, novel and green-extractive techniques (pressurized solvent, supercritical CO₂, and subcritical water extractions) were used to obtain three new extracts from sweet cherry stems, a byproduct generated by the food industry. The extracts were characterized by high-performance liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS), and 57 compounds, mainly flavonoids but also organic and phenolic acids, fatty acids, and terpenes, were identified. After analytical characterization, a multistep screening approach, including antioxidant, enzymatic, and photoprotective cellular studies, was used to select the best extract according to its benefits of interest to the cosmetics industry. The extract obtained with supercritical CO₂ presented the best characteristics, including a wide antioxidant capacity, especially against lipid peroxyl and ^•OH free radicals, as well as relevant photoprotective action and antiaging properties, making it a potential new ingredient for consideration in the development of new cosmetics.

Recent advances in extracting phenolic compounds from food and their use in disease prevention and as cosmetics

Phenolic compounds in plants are essential components of human nutrition, which provide various health benefits. However, some missing links became the research in phenolic compounds structures and potential applications in a challenging work. Despite universal extraction methods with mixtures of different organic solvents are generally adopted in the analysis of phenolic compounds, a need for establish a specific procedure is still open. The great heterogeneity in food and food by-products matrices and the lack of standardized methods which combine chromatographic with spectrophotometric techniques to calculate the amount of phenolic compounds joined with the absence of specific standards hamper to accurate know the real amount of phenolic compounds. Indeed, the high complexity in nature and chemistry of phenolic compounds clearly difficult to establish a daily intake to obtain certain healthy outcomes. Hence, despite the potential of phenolic compounds to use them in cosmetic and healthy applications have been widely analyzed, some concerns must be considered. The chemical complexity, the interactions between phenolic compounds and other food components and the structural changes induced by food processing joined with the lack in the understanding of phenolic compounds metabolism and bioavailability undergo the need to conduct a comprehensive review of each factors influencing the final activity of phenolic compounds. This paper summarizes the potential of phenolic compounds for disease prevention and cosmetics production, as well as their many other uses derived from their antioxidant activity. This paper illustrates the potential of phenolic compounds for disease prevention and cosmetics production, as well as their many other uses derived from their antioxidant activity.

Protective effect of d-tetramannuronic acid tetrasodium salt on UVA-induced photo-aging in HaCaT cells

UVA radiation from the sun is the main external stimulus in the pathogenesis of skin photo-aging. This process is associated with cellular oxidative stress. Here we aim at showing the protective effect of d-Tetramannuronic Acid Tetrasodium Salt (M4), a natural product, against UVA (30J/cm²) irradiation-induced oxidative stress and photo-aging in HaCaT cells, and to reveal the molecular mechanism underlying the protective efficacy. M4 pretreatment significantly increased HaCaT cell viability and MMP, suppressing UVA-induced ROS generation. Moreover, M4 treatment prevented the UVA-induced photo-aging of HaCaT cells (the reduction of cell viability, mitochondria dysfunction, and SIRT1/pGC-1α deregulation). Notably, the anti-photo-aging potential of M4 was directly associated with the increased expression of MMP and SIRT1, which was followed by the up-regulation of pGC-1α, D-LOOP, and Mt-TFA, and the transcriptional activation of NRF1/NRF2. Therefore, M4 is useful for the protection of skin cells from UVA-induced photo-aging.

Protective Effect of L-Hexaguluroic Acid Hexasodium Salt on UVA-Induced Photo-Aging in HaCaT Cells

This study aimed to show the α-L-Hexaguluroic acid hexasodium salt (G6) protective effect against UVA-induced photoaging of human keratinocyte cells. We found that G6 localized to the mitochondria and improved mitochondrial functions. G6 increased respiratory chain complex activities, which led to increased cellular ATP content and NAD+/NADH ratio. Thus, G6 alleviated the oxidative stress state in UVA-irradiated cells. Moreover, G6 can regulate the SIRT1/pGC-1α pathway, which enhanced the cells' viability and mitochondria energy metabolism. Notably, the anti-photoaging potential of G6 was directly associated with the increased level of MMP and SIRT1, which was followed by the upregulation of pGC-1α, D-LOOP, and Mt-TFA, and with the transcriptional activation of NRF1/NRF2. Taking all of the results together, we conclude that G6 could protect HaCaT cells from UVA-induced photo-aging via the regulation of mitochondria energy metabolism and its downstream signaling pathways.

A Potato Peel Extract Stimulates Type I Collagen Synthesis via Akt and ERK Signaling in Normal Human Dermal Fibroblasts

The ability of dermal fibroblasts to synthesize collagen decreases with ages. The integrity of collagen fibers severely decreases in aged skin, causing its characteristic morphological changes such as wrinkles and sagging. To prevent and improve skin aging, the stimulation of collagen synthesis in dermal fibroblasts is important. Potato peels contain many biofunctional compounds, but not much is known about their effects on human skin physiology. To characterize the potential effects of a potato peel extract (PPE) against skin aging, we examined its effects on the synthesis of type I collagen by normal human dermal fibroblasts (NHDFs). Treatment with the PPE significantly increased the expression of type I collagen mRNA in NHDFs and their secretion of type I collagen. To elucidate the mechanism involved, we examined the signaling pathway controlled by transforming growth factor-β (TGF-β), which regulates the synthesis of type I collagen. Treatment of NHDFs with the PPE significantly increased the expression of TGF-β receptor mRNA. TGF-β signaling involves Smad-dependent and Smad-independent pathways, like phosphatidylinositol-3 kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK). The PPE did not activate Smad, but significantly activated Akt and ERK. These results demonstrate that the PPE activates PI3K/Akt and MAPK/ERK signals via TGF-β receptors, which stimulate the synthesis of type I collagen in NHDFs. These results suggest that the PPE could be a novel and effective antiaging material.

Anti-Apoptotic and Anti-Inflammatory Activities of Edible Fresh Water Algae Prasiola japonica in UVB-Irradiated Skin Keratinocytes

Skin is the outer tissue layer and is a barrier protecting the body from various external stresses. The fresh water green edible algae Prasiola japonica has antiviral, antimicrobial, and anti-inflammatory properties; however, few studies of its effects on skin-protection have been reported. In this study, Prasiola japonica ethanol extract (Pj-EE) was prepared, and its skin-protective properties were investigated in skin keratinocytes. Pj-EE inhibited ROS production in UVB-irradiated HaCaT cells without cytotoxicity. Pj-EE also suppressed the apoptotic death of UVB-irradiated HaCaT cells by decreasing the generation of apoptotic bodies and the proteolytic activation of apoptosis caspase-3, -8, and -9. Moreover, Pj-EE downregulated the mRNA expression of the inflammatory gene cyclooxygenase-2 (COX-2), the pro-inflammatory cytokine genes interleukin (IL)-1β, IL-8, IL-6, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ, and the tissue remodeling genes matrix metalloproteinase (MMP)-1, -2, -3, and -9. The Pj-EE-induced anti-inflammatory effect was mediated by suppressing the activation of nuclear factor-kappa B (NF-κB) signaling pathway in the UVB-irradiated HaCaT cells. Taken together, these results suggest that Pj-EE exerts skin-protective effects through anti-oxidant, anti-apoptotic, and anti-inflammatory activities in skin keratinocytes.

1,2-Bis[(3-Methoxyphenyl)Methyl]Ethane-1,2-Dicarboxylic Acid Reduces UVB-Induced Photodamage In Vitro and In Vivo

This study investigated the effects and mechanisms of 1,2-bis[(3-methoxyphenyl)methyl]ethane-1,2-dicarboxylic acid (S4), a sesamin derivative, on anti-inflammation and antiphotoaging in vitro and in vivo. Human skin fibroblasts were treated with S4 and did not show cytotoxicity under concentrations of 5–50 µM. In addition, S4 also reduced ultraviolet (UV)B-induced intracellular reactive oxygen species (ROS) production. Additionally, S4 inhibited UVB-induced phosphorylation of mitogen-activated protein (MAP) kinases, activator protein-1 (AP-1), and matrix metalloproteinases (MMPs) overexpression. Furthermore, S4 also inhibited UVB-induced Smad7 protein expression and elevated total collagen content in human dermal fibroblasts. For anti-inflammatory activity, S4 inhibited UVB-induced nitric oxide synthase (i-NOS) and cyclooxygenase (COX)-2 protein expression and inhibited nuclear factor-kappaB (NF-ĸB) translocation into the nucleus. S4 ameliorated UVB-induced erythema and wrinkle formation in hairless mice. On histological observation, S4 also ameliorated UVB-induced epidermal hyperplasia and collagen degradation. S4 reduced UVB-induced MMP-1, interleukin (IL)-6, and NF-ĸB expression in the mouse skin. The results indicated that S4 had antiphotoaging and anti-inflammatory activities, protecting skin from premature aging.

Protective Effects of Sesamin against UVB-Induced Skin Inflammation and Photodamage In Vitro and In Vivo

Ultraviolet (UV) exposure has been demonstrated as the most critical factor causing extrinsic skin aging and inflammation. This study explored the protective effects and mechanisms of sesamin against skin photodamage. Sesamin reduced intracellular reactive oxygen species production after UVB irradiation in human dermal fibroblasts. The sesamin treatment attenuated mitogen-activated protein (MAP) kinase phosphorylation and matrix metalloproteinase (MMPs) overexpression induced by UVB exposure, and it significantly enhanced the tissue inhibitor of metalloproteinase-1 protein expression. Sesamin also elevated the total collagen content in human fibroblasts by inhibiting UVB-induced mothers against decapentaplegic homolog 7 (Smad7) protein expression. Sesamin reduced UVB-induced inducible nitric oxide synthase (i-NOS) and cyclooxygenase-2 (COX-2) overexpression and inhibited nuclear factor-kappa B (NF-κB) translocation. Moreover, sesamin may regulate the c-Jun N-terminal kinases (JNK) and p38 MAP kinase pathways, which inhibit COX-2 expression. Sesamin could reduce UVB-induced inflammation, epidermal hyperplasia, collagen degradation, and wrinkle formation in hairless mice. It also reduced MMP-1, interleukin (IL-1), i-NOS, and NF-κB in the mouse skin. These results demonstrate that sesamin had antiphotodamage and anti-inflammatory activities. Sesamin has potential for use as a skin protection agent in antiphotodamage and skin care products.

N-Terminal Acetylation and C-Terminal Amidation of Spirulina platensis-Derived Hexapeptide: Anti-Photoaging Activity and Proteomic Analysis

Ultraviolet (UV) irradiation is a potent inducer for skin photoaging. This paper investigated the anti-photoaging effects of the acetylated and amidated hexapeptide (AAH), originally identified from Spirulina platensis, in (Ultraviolet B) UVB-irradiated Human immortalized keratinocytes (Hacats) and mice. The results demonstrated that AAH had much lower toxicity on Hacats than the positive matrixyl (81.52% vs. 5.32%). Moreover, AAH reduced MDA content by 49%; increased SOD, CAT, and GSH-Px activities by 103%, 49%, and 116%, respectively; decreased MMP-1 and MMP-3 expressions by 27% and 29%, respectively, compared to UVB-irradiated mice. Employing isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics, 60 differential proteins were identified, and major metabolic pathways were determined. Network analysis indicated that these differential proteins were mapped into an interaction network composed of two core sub-networks. Collectively, AAH is protective against UVB-induced skin photoaging and has potential application in skin care cosmetics.

Sesamol Inhibited Ultraviolet Radiation-Induced Hyperpigmentation and Damage in C57BL/6 Mouse Skin

Melanin is synthesized through a series of oxidative reactions initiated with tyrosine and catalyzed by melanogenesis-related proteins such as tyrosinase, tyrosinase-related protein-1 (TRP-1), dopachrome tautomerase (TRP-2), and microphthalmia-associated transcription factor (MITF). Our previous study demonstrated that sesamol inhibited melanin synthesis through the inhibition of the melanocortin 1 receptor (MC1R)/MITF/tyrosinase pathway in B16F10 cells. In this study, sesamol was applied to C57BL/6 mouse skin to understand its activity with respect to skin pigmentation. The results indicated that ultraviolet (UV) B-induced hyperpigmentation in the C57BL/6 mouse skin was significantly reduced by topical application of sesamol for 4 weeks. Sesamol reduced the melanin index and melanin content of the skin. In addition, sesamol elevated the brightness (L* value) of the skin. Sesamol also reduced UVB-induced hyperplasia of epidermis and collagen degradation in dermis. In immunohistochemical staining, topical application of sesamol reduced UVB-induced tyrosinase, TRP-1, TRP-2, and MITF expression in the epidermis of the skin. These results demonstrated that sesamol is a potent depigmenting agent in the animal model.

ATRA protects skin fibroblasts against UV‑induced oxidative damage through inhibition of E3 ligase Hrd1

All-trans retinoic acid (ATRA) can protect fibroblasts against ultraviolet (UV)-induced oxidative damage, however, its underlying molecular mechanism is still unclear. The present study aimed to investigate the role of 3-hydroxy-3-methylglutaryl reductase degradation (Hrd1) in the protective effect of ATRA on human skin fibroblasts exposed to UV. The expression of Hrd1 in human or mice skin was assessed by immunohistochemistry (IHC) staining and western blot analysis. Hrd1 siRNA (si-Hrd1) and Hrd1 recombinant adenoviruses (Ad-Hrd1) were used to downregulate and upregulate Hrd1 expression in fibroblasts, respectively. The interaction between Hrd1 and NF-E2-related factor 2 (Nrf2) was assessed by co-immunoprecipitation (co-IP) and immunofluorescence analysis. The results revealed that Hrd1 expression was increased but Nrf2 expression was decreased in UV-exposed human skin fibroblasts. In addition, ATRA could reverse the increase of Hrd1 expression induced by UV radiation in vivo and in vitro. ATRA or knockdown of Hrd1 could increase Nrf2 expression in fibroblasts exposed to UV radiation, and Hrd1 could directly interact with Nrf2 in skin fibroblasts. Notably, overexpression of Hrd1 abolished the protective effect of ATRA on the UV-induced decrease of Nrf2 expression, the production of reactive oxygen species (ROS) and the decrease of cell viability. In conclusion, the present data demonstrated that ATRA protected skin fibroblasts against UV-induced oxidative damage through inhibition of E3 ligase Hrd1.

Protective effect of 3,5‑dicaffeoyl‑epi‑quinic acid against UVB‑induced photoaging in human HaCaT keratinocytes

Derivatives of caffeoylquinic acid (CQA) have been studied and reported as potent bioactive molecules possessing various health benefits including antioxidant and anti‑inflammatory activities. In the present study, the protective effect of 3,5‑dicaffeoyl‑epi‑quinic acid (DCEQA) isolated from Atriplex gmelinii on UVB‑induced damages was investigated in human HaCaT keratinocytes. The effect of DCEQA against UVB‑induced oxidative stress‑mediated damages was determined measuring its ability to alleviate UVB‑induced elevation of oxidative stress, proinflammatory response and antioxidant enzyme suppression through nuclear factor‑like 2 (Nrf2). Treatment with DCEQA hindered the generation of intracellular reactive oxygen species. Increased levels of proinflammatory cytokines TNF‑α, COX‑2, IL‑6 and IL‑1β following UVB exposure were suppressed by the introduction of DCEQA. Additionally, DCEQA upregulated the mRNA and protein expression of antioxidant enzymes superoxide dismutase‑1 and heme oxygenase‑1 which were inhibited under UVB irradiation. Antioxidant enzyme regulation transcription factor Nrf2 was also upregulated in the presence of DCEQA. These results suggest that DCEQA prevents photoaging via protection of keratinocytes from UVB irradiation by ameliorating the oxidative stress and pro‑inflammatory response.

Protective Effects and Mechanisms of N-Phenethyl Caffeamide from UVA-Induced Skin Damage in Human Epidermal Keratinocytes through Nrf2/HO-1 Regulation

The skin provides an effective barrier against physical, chemical, and microbial invasion; however, overexposure to ultraviolet (UV) radiation causes excessive cellular oxidative stress, which leads to skin damage, DNA damage, mutations, and skin cancer. This study investigated the protective effects of N-phenethyl caffeamide (K36) from UVA damage on human epidermal keratinocytes. We found that K36 reduced UVA-induced intracellular reactive oxygen species (ROS) production and induced the expression of the intrinsic antioxidant enzyme heme oxygenase-1 (HO-1) by increasing the translocation of nuclear factor erythroid 2⁻related factor 2 (Nrf2). K36 could inhibit the phosphorylation of extracellular-signal-regulated kinase (ERK) and c-Jun N-terminal kinases (JNK) and reduce UVA-induced matrix metalloproteinase (MMP)-1 and MMP-2 overexpression; it could also elevate the expression of tissue inhibitors of metalloproteinases (TIMP). In addition, K36 ameliorated 8-hydroxy-2'-deoxyguanosine (8-OHdG) induced by UVA irradiation. Furthermore, K36 could downregulate the expression of inducible nitric oxide synthase (iNOS) and interleukin-6 (IL-6) and the subsequent production of nitric oxide (NO) and prostaglandin E₂ (PGE₂). Based on our findings, K36 possessed potent antioxidant, anti-inflammatory, antiphotodamage, and even antiphotocarcinogenesis activities. Thus, K36 has the potential to be used to multifunctional skin care products and drugs.

Protective Effect of Bovine Elastin Peptides against Photoaging in Mice and Identification of Novel Antiphotoaging Peptides

This study aimed to investigate the protective effects of bovine elastin hydrolysates on UV-induced skin photoaging in mice and to identify the potent antiphotoaging peptides. Results showed that the ingestion of elastin peptides could obviously ameliorate epidermis hyperplasia and fibroblast apoptosis, and increase the content of hydroxyproline and water in photoaging skin in vivo ( p < 0.05). Furthermore, four peptides with elastase inhibitory activity were purified and identified, including GLPY, PY, GLGPGVG, and GPGGVGAL. Interestingly, GLPY and GPGGVGAL exhibited the highest inhibition activity with 58.77% and 42.91% at 10 mΜ, respectively. This might be attributed to the N-terminal Gly, C-terminal Leu, and Pro at the third position of the N-terminus, which showed stronger affinity and interaction with elastase. Moreover, GLPY and GPGGVGAL could also inhibit the apoptosis of fibroblasts effectively at 50 μΜ ( p < 0.01). It suggested that elastin peptides had great potential to prevent and regulate skin photoaging.

Protective effects and mechanisms of Terminalia catappa L. methenolic extract on hydrogen-peroxide-induced oxidative stress in human skin fibroblasts

Background

Oxidative stress plays a crucial role in aging-related phenomenon, including skin aging and photoaging. This study investigated the protective role and possible mechanism of Terminalia catappa L. methanolic extract (TCE) in human fibroblasts (Hs68) against hydrogen peroxide (H₂O₂)-induced oxidative damage.

Methods

Various in vitro antioxidant assays were performed in this study. The effect and mechanisms of TCE on oxidative stress-induced oxidative damage were studied by using western blotting.

Results

The IC₅₀ of TCE was 8.2 μg/mL for 1,1-diphenyl-2-picrylhydrazyl radical scavenging, 20.7 μg/mL for superoxide anion radical scavenging, 173.0 μg/mL for H₂O₂ scavenging, 44.8 μg/mL for hydroxyl radical scavenging, and 427.6 μg/mL for ferrous chelation activities. Moreover, TCE inhibited the H₂O₂-induced mitogen-activated protein kinase signaling pathway, resulting in the inhibition of c-Jun, c-Fos, matrix metalloproteinase (MMP)-1, MMP-3, MMP-9, and cyclooxygenase-2 expression. TCE also increased hemeoxygenase-1 expression inhibited by H₂O₂. Finally, TCE was demonstrated reverse type I procollagen expression in fibroblasts after H₂O₂ treatment.

Conclusions

According to our findings, TCE is a potent antioxidant and protective agent that can be used in antioxidative stress-induced skin aging.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2308-4) contains supplementary material, which is available to authorized users.

Artemisia asiatica ethanol extract exhibits anti-photoaging activity

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia asiatica Nakai is a traditional herbal plant that has long been used in anti-inflammatory, anti-infective and skin protective remedies.

AIM OF THE STUDY

In this study, traditionally known skin-protective activity of Artemisia asiatica Nakai was examined with its ethanol extract (Aa-EE) under various photoaging conditions using skin-originated cells, and the underlying mechanism was also examined using various types of cells.

MATERIALS AND METHODS

Effects of Aa-EE on cell viability, photocytotoxicity, and expression of matrix metalloproteinases (MMPs), cyclooxygenase (COX)-2, and moisturizing factors were measured in B16F10, HEK293, NIH3T3, and HaCaT cells under untreated and ultraviolet B (UVB)-irradiation conditions. Anti-melanogenic effect of Aa-EE was also examined by measuring both melanin content in B16F10 cells and tyrosinase activity. Anti-photoaging mechanism of Aa-EE was explored by determining the activation levels of signaling molecules by immunoblotting analysis.

RESULTS

Aa-EE protected HaCaT cells from UVB irradiation-induced death. Aa-EE increased the expression of a type 1 pro-collagen gene and decreased the expression of matrix metalloproteinases, and COX-2 in NIH3T3 cells induced by UVB. Aa-EE increased the expression of transglutamase-1, hyaluronic acid synthase (HAS)-2, and HAS-3 in HaCaT cells and decreased the production of melanin in α-melanocyte-stimulating hormone-stimulated B16F10 cells by suppressing tyrosinase activity and the expression of tyrosinase, microphthalmia-associated transcription factor, tyrosinase-related protein (TRP)-1 and TRP-2.

CONCLUSION

The results suggest that Aa-EE could be skin-protective remedy with anti-photoaging, anti-apoptotic, skin remodeling, moisturizing, and anti-melanogenesis properties.

Optimization of decolorization process in agar production from Gracilaria lemaneiformis and evaluation of antioxidant activities of the extract rich in natural pigments

Gracilaria lemaneiformis is mainly used as a raw material source for agar industry, and its extract is rich in natural pigments with antioxidant activities. In this study, a solvent reflux extraction method for decolorization of G. lemaneiformis has been developed in agar production. The extraction conditions were optimized as follows: solvent-to-material ratio, 50:1; ethanol concentration, 70%; number of extractions, 3; extraction time, 0.5 h, under which the total antioxidant yield of the extract reached 2.89 ± 0.88 mg/g dried seaweeds. Their IC₅₀ values of DPPH radical scavenging activity, hydroxyl radical scavenging activity and superoxide anion scavenging activity were 21.91 ± 1.8 mg/L, 40.59 ± 1.5 mg/L and 160.87 ± 2.8 mg/L, respectively. Further isolation and spectroscopic analysis of natural pigments suggested the strong antioxidant capacities were attributed to chlorophyll derivatives. The results indicate that the decolorization process was able to improve the agar quality, and the extract containing lots of natural pigments had antioxidant activities which may be used in functional food and cosmetics.

Fisetin Regulates Nrf2 Expression and the Inflammation-Related Signaling Pathway to Prevent UVB-Induced Skin Damage in Hairless Mice

Chronic ultraviolet (UV) exposure may cause skin damage, disrupt skin barrier function, and promote wrinkle formation. UV induces oxidative stress and inflammation, which results in extracellular matrix degradation in the dermis and epidermal hyperplasia. Our previous study demonstrated that fisetin exerts photoprotective activity by inhibiting mitogen-activated protein kinase/activator protein-1/matrix metalloproteinases (MMPs) activation. In this study, fisetin was applied topically to investigate its antiphotodamage effects in hairless mice. The erythema index (a* values) and transepidermal water loss were evaluated to assess skin damage, and immunohistochemical staining was conducted to elucidate the photoprotective mechanism of fisetin. The results revealed that the topical application of fisetin reduced UVB-induced increase in the a* value and wrinkle formation. In addition, fisetin inhibited epidermal hyperplasia and increased the collagen content in the dermis. Fisetin exerted photoprotective activity by inhibiting the expression of MMP-1, MMP-2, and cyclooxygenase-2 and increasing the expression of nuclear factor erythroid 2-related factor. Furthermore, fisetin increased the expression of filaggrin to prevent UVB-induced barrier function disruption. Altogether, the present results provide evidence of the effects and mechanisms of fisetin's antiphotodamage and antiphotoinflammation activities.

N-(4-bromophenethyl) Caffeamide Protects Skin from UVB-Induced Inflammation Through MAPK/IL-6/NF-κB-Dependent Signaling in Human Skin Fibroblasts and Hairless Mouse Skin

Long-term exposure to ultraviolet (UV) irradiation causes skin inflammation and aging. N-(4-bromophenethyl) caffeamide (K36H) possesses antioxidant and antimelanogenic properties. The present study investigated the effects of K36H on UVB-induced skin inflammation in human skin fibroblasts and hairless mice and evaluated the underlying mechanisms. The in vitro results indicated that K36H reduced UVB-induced mitogen-activated protein kinase (MAP kinase) expression. Furthermore, K36H treatment reduced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein expression in UVB-irradiated fibroblasts by regulating IκB and nuclear factor-kappa B (NF-κB) expression. In the animal study, topically applied K36H markedly reduced inflammation and skin thickness and prevented photodamage to the skin of hairless mice. In addition, K36H inhibited the levels of UV-upregulated inflammation-related proteins levels such as IL-1, iNOS, and NF-κB in the dermis of hairless mice. Our findings demonstrated the antioxidant and anti-inflammatory properties of K36H in human skin fibroblasts and hairless mice. Therefore, K36H can be developed as an antiphotodamage and antiphotoinflammation agent.