Search Results (639)

Essential oils (EOs) constitute intricate mixtures of volatile phytochemicals that have garnered significant attention due to their multifaceted biological effects. Notably, the presence of bioactive constituents capable of inhibiting tyrosinase enzyme activity and scavenging reactive oxygen species (ROS) underpins their potential utility in skin-related applications, particularly through the modulation of melanin biosynthesis and protection of skin-relevant cells from oxidative damage—a primary contributor to hyperpigmentation disorders. Zingiber officinale Rosc. (ginger) and Humulus lupulus L. (hop) are medicinal plants widely recognized for their diverse pharmacological properties. To the best of our knowledge, this study provides the first report on the synergistic interactions between essential oils derived from these species (referred to as EOZ and EOH) offering novel insights into their combined bioactivity. The purpose of this study was to evaluate essential oils extracted from ginger rhizomes and hop strobiles with respect to the following: (1) chemical composition, determined by gas chromatography–mass spectrometry (GC-MS); (2) tyrosinase inhibitory activity; (3) capacity to inhibit linoleic acid peroxidation; (4) ABTS^•+ radical scavenging potential. Furthermore, the study utilizes both the combination index (CI) and dose reduction index (DRI) as quantitative parameters to evaluate the nature of interactions and the dose-sparing efficacy of essential oil (EO) combinations. GC–MS analysis identified EOZ as a zingiberene-rich chemotype, containing abundant sesquiterpene hydrocarbons such as α-zingiberene, β-bisabolene, and α-curcumene, while EOH exhibited a caryophyllene diol/cubenol-type profile, dominated by oxygenated sesquiterpenes including β-caryophyllene-9,10-diol and 1-epi-cubenol. In vitro tests demonstrated that both oils, individually and in combination, showed notable anti-tyrosinase, radical scavenging, and lipid peroxidation inhibitory effects. These results support their multifunctional bioactivity profiles with possible relevance to skin care formulations, warranting further investigation. Full article

Ultraviolet B (UVB) radiation is a key factor in the overproduction of melanin in the skin. Melanocytes produce melanin through melanogenesis to protect the skin from UVB radiation-induced damage. However, excessive melanogenesis can lead to hyperpigmentation and increase the risk of malignant melanoma. Tyrosinase is the rate-limiting enzyme in melanogenesis; it catalyzes the oxidation of tyrosine to 3,4-dihydroxy-L-phenylalanine and subsequently to dopaquinone. Thus, inhibiting tyrosinase is a promising strategy for preventing melanogenesis and skin hyperpigmentation. White mulberry (Morus alba L.) is rich in antioxidants, and mulberry fruit extracts have been used as cosmetic skin-lightening agents. However, data on the capacity of mulberry fruit extracts to inhibit tyrosinase under UVB radiation-induced melanogenic conditions remain scarce, especially in an in vivo model. In this study, we evaluated the effects of a mulberry crude extract (MCE) on UVB radiation-induced melanogenesis in B16F10 melanoma cells and zebrafish embryos. The MCE significantly reduced tyrosinase activity and melanogenesis in a dose-dependent manner without inducing cytotoxicity. These effects are likely attributable to the antioxidant constituents of the extract. Our findings highlight the potential of this MCE as an effective tyrosinase inhibitor for the prevention of UVB radiation-induced skin hyperpigmentation. Full article

Aramid fibre has become a critical material for individual soft body armour due to its lightweight nature and exceptional impact resistance. To investigate its energy absorption mechanism, quasi-static and dynamic tensile experiments were conducted on Kevlar^® 29 plain-woven fabric using a universal material testing machine and a Split Hopkinson Tensile Bar (SHTB) apparatus. Tensile mechanical responses were obtained under various strain rates. Fracture morphology was characterised using scanning electron microscopy (SEM) and ultra-depth three-dimensional microscopy, followed by an analysis of microstructural damage patterns. Considering the strain rate effect, a viscoelastic constitutive model was developed. The results indicate that the tensile mechanical properties of Kevlar^® 29 plain-woven fabric are strain-rate dependent. Tensile strength, elastic modulus, and toughness increase with strain rate, whereas fracture strain decreases. Under quasi-static loading, the fracture surface exhibits plastic flow, with slight axial splitting and tapered fibre ends, indicating ductile failure. In contrast, dynamic loading leads to pronounced axial splitting with reduced split depth, simultaneous rupture of fibre skin and core layers, and fibrillation phenomena, suggesting brittle fracture characteristics. The modified three-element viscoelastic constitutive model effectively captures the strain-rate effect and accurately describes the tensile behaviour of the plain-woven fabric across different strain rates. These findings provide valuable data support for research on ballistic mechanisms and the performance optimisation of protective materials. Full article

Skin aging is characterized by compromised epidermal homeostasis and dermo-epidermal junction (DEJ) integrity, resulting in reduced stem cell potential and impaired tissue regeneration. This study investigated the effects of Andrographis paniculata extract (APE) on keratinocyte stem cells (KSCs) and DEJ composition in human skin. Using human skin explants and cell culture models, we demonstrated that APE treatment enhances DEJ composition by increasing Collagen IV and Laminin production while decreasing MMP-9 expression, without altering epidermal structure or differentiation. In the same model, APE preserved stemness potential by upregulating markers related to niche components (collagen XVII and β1-integrin), proliferation (Ki-67 and KRT15), and stem cell capacity (Survivin and LRIG1). In vitro studies revealed that APE selectively stimulated KSC proliferation without affecting transit amplifying cells and promoted Collagen IV and Laminin secretion, particularly in KSCs. Furthermore, in a co-culture model simulating a compromised DEJ (UVB-induced), APE increased Laminin production in KSCs, suggesting a protective effect against photo-damage. These findings indicate that APE enhances DEJ composition and preserves stem cell potential, highlighting its promise as a candidate for skin anti-aging strategies targeting stem cell maintenance and extracellular matrix stability to promote skin regeneration and repair. Full article

Alcohol dependency is a complex and chronic condition that negatively impacts multiple organ systems, including the skin. A key pathological factor in this process is oxidative stress, leading to progressive cellular damage, chronic inflammation, and accelerated cutaneous aging. Alcohol metabolism generates reactive oxygen species (ROS), which overwhelm endogenous antioxidant defenses and contribute to a range of skin alterations, including nonspecific changes such as xerosis, erythema, and wrinkle formation, as well as inflammatory and neoplastic skin disorders. Additionally, alcohol-induced alterations of the skin microbiome may further exacerbate skin barrier dysfunction and inflammatory responses. This review explores the biochemical mechanisms and skin microbiome alterations linking alcohol-induced oxidative stress to skin damage and disease. Furthermore, it evaluates the therapeutic potential of antioxidant-based interventions, both natural and synthetic. Antioxidants may offer protective and regenerative effects by scavenging free radicals, modulating inflammatory responses, and enhancing skin barrier function. The paper aims to provide a comprehensive overview of the molecular and microbial interplay between alcohol, oxidative stress, and skin health, while identifying future directions for targeted antioxidant therapy in individuals with alcohol dependency. Full article

Objectives: Sialic acid (SA), a naturally occurring compound abundantly found in birds’ nests, holds immense promise for skincare applications owing to its remarkable biological properties. However, its low bioavailability, poor stability, and limited skin permeability have constrained its widespread application. Methods: To overcome these challenges, SA was encapsulated within nanoliposomes (NLPs) by the high-pressure homogenization technique to develop an advanced and efficient transdermal drug delivery system. The skincare capabilities of this novel system were comprehensively evaluated across multiple experimental platforms, including in vitro cell assays, 3D skin models, in vivo zebrafish studies, and clinical human trials. Results: The SA-loaded NLPs (SA-NLPs) substantially improved the transdermal penetration and retention of SA, facilitating enhanced cellular uptake and cell proliferation. Compared to free SA, SA-NLPs demonstrated a 246.98% increase in skin retention and 1.8-fold greater cellular uptake in HDF cells. Moreover, SA-NLPs protected cells from oxidative stress-induced damage, stimulated collagen synthesis, and effectively suppressed the secretion of matrix metalloproteinases, tyrosinase activity, and melanin production. Additionally, zebrafish-based assays provided in vivo evidence of the skincare efficacy of SA-NLPs. Notably, clinical evaluations demonstrated that a 56-day application of the SA-NLPs-containing cream resulted in a 4.20% increase in L*, 7.87% decrease in b*, 8.45% decrease in TEWL, and 4.01% reduction in wrinkle length, indicating its superior brightening, barrier-repair, and anti-aging effects. Conclusions: This multi-level, systematic investigation strongly suggests that SA-NLPs represent a highly promising transdermal delivery strategy, capable of significantly enhancing the anti-aging, barrier-repair, and skin-brightening properties of SA, thus opening new avenues for its application in the fields of dermatology and cosmeceuticals. Full article

Background/Objectives: Ultraviolet B (UVB) radiation contributes significantly to skin aging and skin disorders by promoting oxidative stress, inflammation, and collagen degradation. Natural antioxidants such as theaflavins and thearubigins from Camellia sinensis L. (black tea) have shown photoprotective effects. This study aimed to optimize the extraction of theaflavins and thearubigins from black tea leaves and evaluate the efficacy of the extract against UVB-induced damage using a transfersome-based topical formulation. Methods: Extraction of theaflavins and thearubigins was optimized via response surface methodology (Box-Behnken Design), yielding an extract rich in active polyphenols. This extract was incorporated into transfersomes that were characterized for size, polydispersity, zeta potential, storage stability, and entrapment efficiency. Human dermal fibroblasts (NHDF) were used to assess cytotoxicity, protection against UVB-induced viability loss, collagen degradation, and expression of inflammatory (IL6, COX2, iNOS) and matrix-degrading (MMP1) markers. Cellular uptake of the extract’s bioactive marker compounds was measured via LC-MS/MS. Results: The transfersomes (~60 nm) showed a good stability and a high entrapment efficiency (>85%). The transfersomes significantly protected NHDF cells from UVB-induced cytotoxicity, restored collagen production, and reduced gene expression of MMP1, IL6, COX2, and iNOS. Cellular uptake of key extract’s polyphenols was markedly enhanced by the nanoformulation compared to the free extract. Conclusions: Black tea extract transfersomes effectively prevented UVB-induced oxidative and inflammatory damage in skin fibroblasts. This delivery system enhanced bioavailability of the extract and cellular protection, supporting the use of the optimized extract in cosmeceutical formulations targeting photoaging and UV-induced skin disorders. Full article

Environmental exposure to per- and polyfluoroalkyl substances (PFASs) has been increasingly associated with skin disorders, including atopic dermatitis (AD); however, the underlying molecular mechanisms remain unclear. This study aimed to evaluate the effects of perfluorononanoic acid (PFNA) and perfluorooctanoic acid (PFOA)—two widely detected PFASs—on epidermal function and gene expression in Human Epithelial Keratinocyte, neonatal (HEKn). We assessed cell viability, morphology, and transcriptomic changes using in vitro assays and RNA-seq analysis from a neonatal cohort. PFASs induced dose-dependent cytotoxicity and downregulation of barrier-related genes. Ingenuity pathway analysis identified calcitriol as a suppressed upstream regulator. Functional validation revealed that calcitriol partially reversed the PFAS-induced suppression of antimicrobial peptide genes. These findings support the hypothesis that PFASs may contribute to AD-like skin pathology by impairing vitamin D receptor signaling and antimicrobial defense, and calcitriol demonstrates potential as a protective modulator. This study provides mechanistic insights into the impact of environmental toxicants on skin homeostasis and suggests a potential protective role for calcitriol in PFAS-induced skin barrier damage. Full article

Background: Vitiligo, a chronic depigmentation disorder driven by oxidative stress and immune dysregulation, remains poorly understood mechanistically. The Keap1/NRF2/ARE pathway is critical for melanocyte protection against oxidative damage; however, the role of Cullin-3 (CUL3), a scaffold for E3 ubiquitin ligases that regulate NRF2 degradation, and its interplay with inflammatory mediators in vitiligo pathogenesis are underexplored. This study investigates CUL3, NRF2, and the associated regulatory networks in vitiligo, integrating clinical profiling and computational docking to identify therapeutic targets. Methods: A case-control study compared non-segmental vitiligo patients with age-/sex-matched controls. Lesional skin biopsies were analyzed by qRT-PCR for the expression of CUL3, NRF2, miRNA-146a, FOXP3, NF-κB, IL-6, TNF-α, and P53. Molecular docking was used to evaluate vitexin’s binding affinity to Keap1, validated by root mean square deviation (RMSD) calculations. Results: Patients with vitiligo exhibited significant downregulation of CUL3 (0.27 ± 0.03 vs. 1 ± 0.58; p = 0.013), NRF2 (0.37 ± 0.26 vs. 1 ± 0.8; p = 0.001), and FOXP3 (0.09 ± 0.2 vs. 1 ± 0.3; p = 0.001), alongside the upregulation of miRNA-146a (4.7 ± 1.9 vs. 1 ± 0.8; p = 0.001), NF-κB (4.7 ± 1.9 vs. 1 ± 0.5; p = 0.001), IL-6 (2.8 ± 1.5 vs. 1 ± 0.4; p = 0.001), and TNF-α (2.2 ± 1.1 vs. 1 ± 0.3; p = 0.001). P53 showed no differential expression (p > 0.05). Docking revealed a strong binding of vitexin to Keap1 (RMSD: 0.23 Å), mirroring the binding of the control ligand CDDO-Im. Conclusions: Dysregulation of the CUL3/Keap1/NRF2 axis and elevated miRNA-146a levels correlate with vitiligo progression, suggesting a role for oxidative stress and immune imbalance. Vitexin’s high-affinity docking to Keap1 positions it as a potential modulator of the NRF2 pathway, offering novel therapeutic avenues. This study highlights the translational potential of targeting the ubiquitin–proteasome and antioxidant pathways in the management of vitiligo. Full article

Aloin, a kind of active phenolic component, is sourced from Aloe vera. Recently, the determination of aloin has received enormous attention, owing to its positive performance (including anti-tumor, antibacterial, detoxification, liver protection, anti-stomach damage, and skin protection activities) and painful side effects (increased carcinogenicity caused by excessive use of aloin) impacting human health. This investigation was inspired by the good fluorescence properties of carbon dots (CDs); CD-based sensors have aroused a great deal of interest due to their excellent sensitivity and selectivity. Thus, it is of great significance to develop novel CD-based sensors for aloin determination. Herein, N,F-CDs were designed and synthesized through a convenient hydrothermal strategy; the synthesized N,F-CDs possessed good fluorescence performance and a small particle size (near 4.3 nm), which demonstrated the successful preparation of N,F-CDs. The resulting N,F-CDs possessed a large Stokes shift and could emit a highly stable green fluorescence. The fluorescence of the N,F-CDs could be effectively quenched by aloin through the inner filter effect. Furthermore, the synthesis procedure was easy to operate. Finally, the N,F-CD-coated test strips were fabricated and combined with a miniaturized fluorimeter for the fluorescence detection of aloin via the inner filter effect for the first time. The N,F-CD-coated test strips were fabricated and used for the fluorescence sensing of aloin, and the results were compared with a typical ultraviolet (UV) method. The N,F-CD-coated test strips exhibited high recovery (96.9~106.1%) and sensitivity (31.8 nM, n = 3), good selectivity, low sample consumption (1 μL), high speed (5 min), good stability, and anti-interference properties. The results indicate that N,F-CD-coated test strips are applicable for the quantitative determination of aloin in bovine serum, orange juice, and urine samples. Full article

Viola philippica (VP), a traditional Chinese medicinal herb widely used for its antibacterial and antioxidant properties, has recently garnered attention for its potential in skin photoprotection. VP was extracted using glycerol (GLY), 1,3-propanediol (PDO), and 1,3-butanediol (BDO) at concentrations of 30%, 60%, and 90% (w/w) to evaluate its antioxidant and UV-protective properties. The total phenolic content (TPC) and total flavonoid content (TFC) of the nine extracts ranged from 34.73 to 71.45 mg GAEs/g and from 26.68 to 46.68 mg REs/g, respectively, with the highest TPC observed in 90% PDO and the highest TFC in 60% GLY. Antioxidant assays revealed IC₅₀ values of 0.49–1.26 mg/mL (DPPH), 0.10–0.19 mg/mL (ABTS), and 1.58–460.95 mg/mL (OH). Notably, the 60% GLY, 30% PDO, and 90% PDO extracts demonstrated notable protective effects against UVB-induced cell damage, reducing intracellular ROS levels and preventing DNA damage. RNA-seq analysis revealed that the protective effects were associated with the modulation of key molecular pathways, including neutrophil extracellular trap formation and TNF, IL-17, and HIF-1 signaling. These findings suggest that Viola philippica polyol extracts, particularly those using 60% GLY, 30% PDO, and 90% PDO, have promising potential for skin photoprotection and could be utilized as natural antioxidants in cosmetic formulations. Full article

Ultraviolet A (UVA) radiation has been identified as a significant factor contributing to skin photoaging and skin diseases, operating through the excessive generation of reactive oxygen species (ROS) and the subsequent induction of DNA damage. Plant-derived antioxidants have demonstrated efficacy in mitigating UVA-induced damage; nevertheless, their instability limits their therapeutic potential. This study investigates the mechanisms of antioxidant and cytoprotective effects of squalane (Sq), a stable, plant-derived triterpene, in human dermal fibroblasts (HDFs) exposed to UVA radiation. Sq was administered at concentrations ranging from 0.005% to 0.015% prior to UVA exposure (10 J/cm²). It has been found that Sq counteracted UVA-induced ROS formation, decreased the level of reduced thiol groups, activated apoptosis, and inhibited DNA biosynthesis. Immunofluorescence analysis revealed that Sq suppressed the UVA-induced expression of p53, caspase-3, caspase-9, and PARP, while restoring the activity of the pro-survival p-Akt/mTOR pathway. The findings indicate that Sq exerts protective effects on UVA-induced fibroblast damage through a combination of antioxidant and anti-apoptotic mechanisms. Full article

UVB skin pathology is initiated by reactive oxygen species (ROS), differentiating this condition from other inflammatory diseases involving first the immune cell activation by danger or pathogen molecular patterns followed by oxidative stress. Resolvin D2 (RvD2) has been found to reduce inflammation in preclinical models. However, whether or not RvD2 reduces skin pathology caused by UVB irradiation is not yet known. Therefore, the efficacy of RvD2 on skin pathology triggered by UVB irradiation in female hairless mice was assessed. RvD2 (0.3, 1 or 3 ng/mouse, i.p.) was found to protect the skin against UVB inflammation, as observed in the reduction in edema (46%), myeloperoxidase activity (77%), metalloproteinase-9 activity (39%), recruitment of neutrophils/macrophages (lysozyme⁺ cells, 76%) and mast cells (106%), epidermal thickening (93%), sunburn cell formation (68%), collagen fiber breakdown (55%), and production of cytokines such as TNF-α (100%). Considering the relevance of oxidative stress to UVB irradiation skin pathologies, an important observation was that the skin antioxidant capacity was recovered by RvD2 according to the results that show the ferric reducing antioxidant power (68%), cationic radical scavenges (93%), catalase activity (74%), and the levels of reduced glutathione (48%). Oxidative damage was also attenuated, as observed in the reduction in superoxide anion production (69%) and lipid hydroperoxides (71%). The RvD2 mechanism involved the inhibition of NF-κB activation, as observed in the diminished degradation of IκBα (48%) coupled with a reduction in its downstream targets that are involved in inflammation and oxidative stress, such as COX-2 (66%) and gp91^phox (77%) mRNA expression. In conclusion, RvD2 mitigates the inflammatory and oxidative pathologic skin aggression that is triggered by UVB. Full article

Ultraviolet B (UVB), a component of solar ultraviolet light, is a major contributor to skin photodamage. UVB exposure primarily affects the epidermis, which leads to wrinkle formation, loss of skin elasticity, oxidative stress, and inflammation. Prolonged or intense UVB exposure can increase the risk of skin cancer. Collagen peptides are known as functional foods that improve skin dryness and wound healing. In this study, we aimed to investigate the protective and ameliorative effects of a low-molecular-weight collagen peptide (LMWCP) with a high absorption rate and photodamage. In vitro analysis using human dermal fibroblasts (HDFs) demonstrated that LMWCP promoted skin protection by increasing procollagen type I production, enhancing cell proliferation and migration, and inhibiting MMP-1 activity. Furthermore, LMWCP intake was indicated by improved skin hydration, reduced trans-epidermal water loss (TEWL), and changes in the clinical parameters, including skin elasticity, erythema, and scaling scores in UVB-exposed hairless mice. In the UVB-damaged tissues, an increase in skin elasticity-related enzymes was observed along with a decrease in aging-related and pro-inflammatory gene expression. Histological analysis revealed an increase in collagen content and restoration of dermal thickness. These findings suggested that LMWCP has significant benefits in preventing and improving UVB-induced skin damage. Full article

Rising global temperatures increase skin exposure to heat stress, which can impair skin structure and function. While several cosmetic ingredients have been developed to mitigate heat-induced damage, most primarily aim to enhance hydration or suppress inflammation, lacking mechanistic insights into their action under heat stress. This study assessed E. artemiae-derived SUPER-T and its exosome form, Thermasome, in heat-stressed human skin fibroblasts. Transcriptomic profiling revealed that heat stress upregulated heat-related thermal receptors and downregulated key extracellular matrix (ECM)-related genes. Notably, treatment with SUPER-T upregulated expression of these genes, suggesting a reparative role as a barrier to alleviate heat stress at the dermal–epidermal junction. For its application in a field of cosmetics, SUPER-T encapsulated in exosomes (Thermasome) enhanced the heat resilience, suggesting its better transdermal and heat protective effects. Thermasome further improved skin heat resilience and enhanced ECM gene expression including collagen genes. Our findings provide a mechanistic basis for the development of functional cosmetical materials that target ECM remodeling under heat-stressed conditions. Full article