Search Results (1,791)

Skin aging is primarily driven by oxidative stress, mitochondrial dysfunction, and cell cycle dysregulation. This study investigated the anti-senescence effects of fermented porcine placenta (FPP) and its dipeptides, leucine–glycine (LG) and proline–hydroxyproline (PH), in human epidermal keratinocytes (HEKs), using nicotinamide mononucleotide (NMN) as a reference for nicotinamide adenine dinucleotide (NAD⁺)-related pathways. FPP suppressed senescence-associated β-galactosidase (SA-β-gal) activity and Cyclin-dependent kinase inhibitor 2A (p16) expression while enhancing adenosine triphosphate (ATP) production and sirtuin 1 (SIRT1)–peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) signaling. LG and PH exhibited distinct actions: LG improved redox balance by increasing the NAD⁺/NADH ratio and NAD(P)H quinone oxidoreductase 1 (NQO1) activity, whereas PH modulated cell cycle regulators and upregulated sirtuin 3 (SIRT3) expression. Although both peptides contributed to FPP’s effects, their combination did not fully replicate its overall activity, suggesting synergistic roles of multiple bioactive constituents. These findings highlight FPP as a multifactorial modulator of keratinocyte senescence, acting via mitochondrial and redox-related mechanisms. Full article

Background: Centaurium erythraea Rafn. (C. erythraea) is a medicinal plant traditionally used in European folk medicine for the treatment of wounds, skin inflammations, and other dermatological conditions, in addition to its well-documented systemic antioxidant and anti-inflammatory effects. However, its topical applications remain insufficiently investigated, particularly using plant material collected from Romania. The purpose of this study was to prepare different ointment formulations containing C. erythraea Rafn. extract obtained from the aerial parts of the plant, using various excipients, and to evaluate their in vitro and in vivo efficacy. Methods: The phytochemical profile of C. erythraea extract was characterized using liquid chromatography–tandem mass spectrometry (LC–MS/MS). The lyophilized extract was pre-dissolved in different solubilizing agents—Transcutol^® P (diethylene glycol monoethyl ether), Capryol^® 90 (propylene glycol monocaprylate), or a combination of both—and then incorporated into five ointment formulations. Texture analysis and an in vitro membrane diffusion study were performed. The antioxidant capacity of the formulations was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP), and total phenolic content (TPC) assays. Anti-inflammatory activity was evaluated in vitro using tumor necrosis factor-alpha (TNF-α)-induced interleukin-1 beta (IL-1β) production in human keratinocyte (HaCaT) cells, and in vivo using a carrageenan-induced rat paw edema model. Results: LC–MS/MS identified 18 polyphenolic compounds, with hyperoside (3.78 ± 0.05 µg/mL), protocatechuic acid (1.13 ± 0.06 µg/mL), chlorogenic acid (1.07 ± 0.06 µg/mL), and quercetin (0.53 ± 0.03 µg/mL) as the principal constituents. The formulation containing both Transcutol^® P and Capryol^® 90 exhibited the most pronounced antioxidant activity (65% DPPH inhibition; 69.71 ± 0.83 mg gallic acid equivalent/mL) and significantly reduced IL-1β levels by 45.7% compared to the inflamed control. In vivo, this formulation showed comparable anti-edematous effects to a methylprednisolone ointment. Furthermore, it demonstrated the highest skin permeation efficiency, with a quercetin diffusion coefficient of 35.12 × 10⁻⁵ cm²/min. Conclusions: These findings highlight the therapeutic potential of C. erythraea extract from aerial parts in topical formulations and underscore the enhancing role of Transcutol^® P and Capryol^® 90 in improving both the pharmacodynamic and pharmacokinetic properties of bioactive compounds. Full article

Nigella sativa, or black cumin, is used as a spice in cooking and as a food supplement like seeds or oil for its biological properties, including antioxidant capacity, anti-inflammatory action, and support for the immune system. In the present study, the chemical composition and biological activities of the Nigella sativa seeds’ fatty oil (NS) were investigated. The analytical composition was carried out by several techniques, such as GC-MS spectrometry and ¹H- and ¹³C-NMR spectroscopies using appropriate internal standards. The GC-MS analysis highlighted the presence of palmitic and linoleic acid as major compounds. The antioxidant potential was evaluated through the DPPH radical-scavenging assay, and, furthermore, the NS effect on intracellular reactive oxygen species (ROS) levels was assessed in HaCaT cells (non-tumorigenic human keratinocytes) under oxidative stress induced by hydrogen peroxide. The cytotoxic and genotoxic profiles were evaluated on Caco-2 cells (human colorectal adenocarcinoma cells) using the CCK-8 viability assay and the Comet assay, respectively. Overall, the results demonstrated that NS possessed antioxidant activity, as evidenced by concentration-dependent DPPH radical scavenging and reduced intracellular ROS levels in HaCaT cells under oxidative stress. In Caco-2 colorectal cancer cells, NS induced significant cytotoxicity and DNA damage at higher concentrations, suggesting potential genotoxic effects. These findings support the dual role of NS as a natural antioxidant and a promising candidate for nutraceutical and dermatological applications, including those targeting oxidative stress-related conditions and cancer. Full article

Polianthes tuberosa L. (PT) flower extracts exhibit considerable bioactivities, yet their application is often constrained by limited bioavailability and efficacy. In this study, fermentation of PT (FPT) using Rhodosporidium toruloides significantly enhanced its phytochemical profile, doubling the total phenol content (697.22 ± 7.51 μg/mL in FPT versus (vs.) 347.61 ± 5.89 μg/mL in non-fermented extract (NF)) and increasing flavonoids by onefold relative to NF (381.44 ± 6.50 μg/mL in FPT vs. 190.25 ± 4.75 μg/mL in NF), resulting in a substantial improvement in radical scavenging capacity (DPPH: 47.59 ± 1.55%; ABTS: 89.87 ± 1.39%). In UVB-irradiated the human keratinocyte cell line, FPT demonstrated superior efficacy over NF by effectively reducing reactive oxygen species and malondialdehyde levels (1.29 ± 0.08 ng/mL at 0.4 mg/mL FPT vs. 1.5 ± 0.1 ng/mL with NF), while concurrently elevating the activity of key antioxidant enzymes. Using human dermal fibroblasts, FPT was further shown to possess notable anti-glycation and anti-carbonylation properties, significantly inhibiting carboxymethyl lysine formation (90.6 ± 3.6% reduction) and protein carbonylation (86.5 ± 2.2% reduction). It also suppressed senescence-associated β-galactosidase activity (67.9 ± 3.0% inhibition), downregulated matrix metalloproteinase-1 expression (62.5 ± 5.1% reduction), and stimulated type I collagen synthesis (166.5 ± 4.2% recovery). Additionally, FPT markedly inhibited UVB-induced melanogenesis in B16F10 melanoma cells by reducing melanin content (36.0 ± 5.3%) and tyrosinase activity (45.7 ± 1.2%), through the downregulation of critical melanogenic genes, including melanocortin 1 receptor, microphthalmia-associated transcription factor, and tyrosinase. Full article

The occurrence and impact of cellular senescence on skin aging and hyperpigmentation is an ongoing area of exploration, encompassing both intrinsic and extrinsic stressors. Traditionally, research has focused on melanocyte and fibroblast senescence due to their slower turnover compared to keratinocytes. In this study, we identified the accumulation of p16, a senescence marker, in keratinocytes from biopsies of multiple spot types. We explored their impact using doxorubicin-induced senescent keratinocytes in vitro. Conditioned media from these senescent keratinocytes stimulated melanocyte dendricity, a hallmark of hyperpigmented spots. Transcriptomic analysis of senescent keratinocytes identified two key senescence-induced factors: Insulin-like Growth Factor-Binding Protein 3 (IGFBP3) and Nerve Growth Factor (NGF). IGFBP3 and NGF ligand treatment enhanced melanin synthesis by 33% and 17%, and dendricity by 23% and 14%, respectively, in human melanocyte cultures. These findings suggest that keratinocyte senescence contributes to spot formation by mediating melanocyte activation through IGFBP3 and NGF. Furthermore, we evaluated skincare ingredients such as sucrose dilaurate, glabridin, and niacinamide in neutral and low pH solutions, demonstrating their efficacy in reducing the secretion of these ligands, thereby offering potential cosmetic benefits. This study provides insights into the mechanisms of spot formation and highlights promising strategies for managing pigmentation disorders. Full article

Background/Objectives: The rapid emergence of antibiotic-resistant oral pathogens has rendered many conventional therapies increasingly ineffective. Antimicrobial peptides (AMPs) have emerged as a promising therapeutic alternative due to their unique mechanisms of action and low propensity for inducing resistance. The delivery of novel therapeutic AMPs against oral cavity bacterial infections requires effective pharmaceutical dosage formulations. This study investigated the potential of two liposomal formulations for the association and delivery of the antimicrobial peptide (AMP) LL17-32 against the dental bacterial pathogen Porphyromonas gingivalis. Methods: Liposomes composed of either negatively charged soya lecithin (SL) or neutrally charged dioleoyl-phosphatidylcholine (DOPC) phospholipids were formulated and characterized based on their hydrodynamic size distribution, ζ-potential, morphology, membrane fluidity, peptide association efficiency, stability and release of peptide in vitro under physiological conditions. The characterization of their biological activity included efficiency of bacterial killing, bacterial adherence, and mammalian cell cytotoxicity using human gingival keratinocyte (TIGK) cells. Results: Both liposomal formulations exhibited spherical morphology with hydrodynamic diameters smaller than ~170 nm and demonstrated good colloidal stability. LL17-32 showed high association efficiency with both liposomal membranes, with no detectable LL17-32 in vitro release. In biological assays, peptide-loaded DOPC liposomes exhibited dose-dependent bactericidal activity against P. gingivalis, whereas SL liposomes significantly attenuated the bactericidal effect of LL17-32. Both formulations displayed reduced cytotoxicity toward human gingival keratinocyte (TIGK) cells versus free peptide. Conclusions: These findings suggest that DOPC liposomes represent a promising delivery system for LL17-32 by adhering to P. gingivalis and exhibiting minimal cytotoxicity to mammalian cells. This study emphasises the critical role of lipid charge in designing AMP delivery systems for antibacterial applications, while it additionally demonstrates the utility of flow cytometry as a quantitative tool to assess liposome–bacteria association. Full article

This study aimed to use sunflower seeds (SSs) and barbatimão bark (BB) to obtain an oil enriched with phenolic compounds. For this purpose, simultaneous extractions were carried out using different proportions of SSs and BB. Subsequently, the effects of temperature and extraction time were determined. The resulting oils were evaluated for composition and physicochemical properties. BB addition decreased the mass yield by 27% to 56% but increased the total phenolic content by 5 to 13 times. The best SS/BB ratio (3:2.5) was selected for further experiments. Increasing the extraction temperature from 30 to 60 °C and the extraction time from 15 to 60 min led to a 10% increase in oil yield and enhanced the contents of phenolic acids and flavonoids by 1.1 to 10 times. Gallic, quinic, and trans-cinnamic acids were the main phenolics in enriched oils, which exhibited higher antioxidant activity via the DPPH^•, FRAP, and ABTS^•+ methods. Linoleic and oleic acids were identified as the major fatty acids in the tested oils. Enriched oils showed greater thermal stability than their unenriched counterpart. The application of phenolic-enriched oil at concentrations of up to 400 µg/mL did not exert cytotoxic effects on human keratinocyte HaCaT cells. Full article

Obesity, a global health crisis, is linked to chronic low-grade inflammation and an increased risk of developing various chronic diseases, including psoriasis. Probiotics, postbiotics, and fermented foods have shown promise in combating inflammation and obesity. This study aimed to develop and characterize a chicory extract fermented with Bacteroides fragilis (C-B. fragilis) and its supernatant (phyto-postbiotic supernatant, PPS) as potential treatments for obesity, inflammation, and psoriasis. Polyphenols, organic acids, and amino acids were identified in the metabolic profile of C-B. fragilis. PPS and C-B. fragilis extract both revealed potent anti-inflammatory, anti-obesity, and antioxidant activities. In vitro assays highlighted that PPS significantly reduced the production of reactive oxygen species (ROS), the expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-8) in macrophages, and the secretion of IL-1β in LPS-stimulated PBMCs. Moreover, PPS decreased triglyceride content in human adipocytes and modulated the expression of leptin and adiponectin. Regarding psoriasis, PPS reduced pro-inflammatory cytokines (IL-6, IL-1β) in both psoriatic keratinocytes and a co-culture model mimicking the skin-adipose tissue interface. In addition, PPS lowered S100 calcium-binding protein A7 (S100A7) expression in the co-culture model, suggesting a potential role in restoring skin barrier function. In summary, our results highlight the potential of PPS extract (supernatant of chicory fermentation by Bacteroides fragilis) as a promising therapeutic strategy for the management of obesity-related inflammation and psoriasis. Full article

Mycosporine-like amino acids (MAAs) are secondary metabolites of interest for the development of natural sunscreens, owing to their antioxidant activity and ultraviolet radiation (UVR)-absorbing properties. MAA-rich aqueous extracts obtained from the Chilean red alga Mazzaella laminarioides (locally known as luga cuchara) were analyzed by HPLC and loaded into chitosan nanoparticles (CSNPs), with an encapsulation efficiency of 90.1%. The resulting CS nanoformulations (CSNFs) were characterized by FTIR spectroscopy, DLS and TEM microscopy, confirming the presence of nanoparticles with a core diameter of 94 ± 11 nm and FTIR absorption bands accounting for CS functional groups. Pre-treatment of HaCaT keratinocytes with CSNFs conferred complete protection against low-to-moderate UVA doses (5, 10, 15, and 30 J/cm²). Remarkably, cells still retained a protection efficacy of 64.7% under lethal UVA exposure (60 J/cm²), with gene expression evidence suggesting the activation of a compensatory stress response to photo-oxidative damage. CSNFs were also capable of restoring cell viability in post-treatment experiments at UVA doses of 30 J/cm² (100% cell viability) and 60 J/cm² (~43% cell viability). This is the first demonstration that nanoencapsulation of an MAA-rich algal extract yields superior UVA photoprotection in human keratinocytes compared with non-encapsulated MAA-based formulations, contributing to the effort of developing eco-friendly sunscreens. Full article

Postbiotics are bioactive microbial metabolites recognized for their potential to support skin health and balance the microbiota. In this study, nonwoven fabrics and adult diaper prototypes, with and without postbiotic incorporation, were evaluated for their effects on skin microbiota, epidermal integrity, and cytotoxicity. In vitro assays using reconstructed human epidermis and keratinocyte cell lines demonstrated that postbiotic-containing samples maintained high tissue and cell viability. Microbiota diversity analyses confirmed that postbiotic formulations maintained a favorable ratio of Staphylococcus epidermidis to Staphylococcus aureus. Collectively, these findings indicate that ATA-coded postbiotic-embedded nonwoven and adult diaper prototypes are skin microbiota-friendly, safe for epidermal contact, and stable in their bioactive compound content. These results underscore the potential of postbiotics as functional agents in personal hygiene products to promote skin health. Full article

Reliable methods for the isolation and culture of human eccrine sweat gland cells (SGCs) are essential for studying glandular biology and developing tissue-engineered skin substitutes (TESs) that restore full skin function. However, maintaining the glandular phenotype of SGCs in vitro remains a major challenge. In this study, we present an optimized isolation protocol combining enzymatic digestion with mechanical separation to improve SGC yield and purity, while also enabling keratinocyte isolation from a single human skin biopsy. We then evaluated two culture strategies, 2D monolayers and 3D spheroids, to determine their impact on SGC identity and proliferation. While 2D culture supported cell expansion, SGCs and keratinocytes exhibited highly similar marker expression profiles, with the absence of functional SGC markers (AQP5, α-SMA) reflecting a shift toward less differentiated phenotypes. In contrast, SGCs cultured in 3D spheroids preserved the expression of SGC-specific markers (AQP5, K18, α-SMA), distinguishing them from keratinocytes; however, their growth and structural organization were suboptimal under these 3D conditions. Moreover, SGCs expanded in 2D did not regain their glandular features when reintroduced into 3D culture, suggesting potential limitations in phenotype recovery. These results highlight the need for improved culture systems that maintain SGC identity while supporting expansion. Advancing such methods is a critical step toward integrating functional sweat glands into TESs and achieving complete skin regeneration for clinical applications. Full article

A corneal abrasion results from the disruption or loss of cells in the corneal epithelium. If inadequately treated, it can compromise visual clarity. The wound healing process of a corneal abrasion involves epithelial migration, proliferation and adhesion. Clitoria ternatea flower extract (CTE) is rich in flavonoids, anthocyanins and other bioactive compounds. It has antioxidant, anti-inflammatory and wound-healing properties. This study explores the potential of CTE to be used as a natural supplement to improve corneal wound healing. Phytochemical profiling via LC–MS identified a total of 51 distinct bioactive constituents. The anthocyanin content, quantified in terms of cyanidin-3-glucoside equivalent, was quantified at 33.06 mg per gram of extract. The extract exhibited 33.8% DPPH radical scavenging activity and a total polyphenol content equivalent to 24.14 mg/g gallic acid. Human telomerase-immortalized corneal epithelial (hTCEpi) cells maintained in keratinocyte basal medium were utilized to determine cytotoxicity and wound-healing effects. The optimal extract concentration of 0.08 mg/mL, quantified via MTT assay, resulting in enhanced cell viability. Scratch assays demonstrated a higher percentage of wound closure in the CTE-treated group at 6 and 12 h relative to the untreated group, with statistical significance (p < 0.05). The gene expressions of CK3 and Cx43, quantified via qRT-PCR, showed no significant differences between groups. However, within the CTE-treated group, CK3 expression increased at 12 h relative to 0 h and 6 h, and Cx43 expression rose significantly at 12 h compared with 0 h (p < 0.05). Immunofluorescence confirmed positive protein expression of both markers. These findings suggest that CTE possesses potent antioxidant properties and promotes corneal epithelial wound healing through upregulation of CK3 and Cx43 in vitro. Full article

Background: Cannabinoids, such as tetrahydrocannabinol (∆-9-THC) and cannabidiol (CBD) have been proposed for topical medicinal use as a treatment for tissue inflammation. In this context, keratinocytes are the first cells that encounter cannabinoids. The present study evaluated the dose–response relationship between different concentrations of THC and CBD and their effects on human skin and gingival keratinocyte growth and migration, to identify suitable non-toxic concentrations of cannabinoids. Methods: Human gingival and skin keratinocytes were exposed to CBD or THC at different concentrations for 24 h, and then cell adhesion, morphology, and growth/viability were assessed. The effects of cannabinoids on keratinocyte migration were evaluated at 6, 12, and 24 h. Cytotoxicity of CBD and THC against keratinocyte cells was assessed using an LHD cytotoxicity test. Cell metabolic profiles were evaluated using Mito and Glyco Stress Assays. The anti-inflammatory effects of cannabis derivatives were assessed against LPS-stimulated keratinocytes. Data analysis was performed by one-way ANOVA. Results: Only high concentrations (10 and 20 μg/mL) of CBD and THC were cytotoxic to gingival and skin keratinocytes, reduced cell adhesion and growth, and were associated with a delay in cell migration after wounding. Cells exposed to high concentrations (20 μg/mL) of cannabinoids displayed high levels of lactate dehydrogenase (LDH) activity and changes in mitochondrial activities. CBD induced a metabolic shift in skin keratinocyte cells toward glycolysis, while reducing mitochondrial oxidative phosphorylation. In contrast, THC did not alter the metabolic profile of skin keratinocytes. Interestingly, both CBD and THC significantly reduced the LPS-induced inflammatory response by decreasing secretion of IL-6 and IL-8 by gingival and skin keratinocytes. Conclusions: Gingival and skin keratinocytes interact differently with cannabinoids. Only high concentrations of cannabinoids were cytotoxic, suggesting that the use of low concentrations of CBD and THC for topical medicinal applications may help control tissue inflammation. Full article

Background/Objectives: In this study, we focused on a mixed microbial culture of Lactobacillus paracasei, Pichia membranifaciens, and Saccharomyces cerevisiae (LS) as a new probiotic and examined the therapeutic and preventive effects of topical treatment with LS in a mouse model of atopic dermatitis (AD). Methods: Immunomodulatory effects of LS were examined with murine dendritic cell lines (DC2.4) by measuring the interleukin (IL)-10 and tumor necrosis factor (TNF) α levels. The anti-inflammatory effects of LS were evaluated in stimulated human epidermal keratinocytes (HaCaTs) by focusing on the production of IL-8 and thymus and activation-regulated chemokine (TARC). Therapeutic and preventive properties of topical treatment with LS (10%) were finally examined in a mouse model of AD developed by topical sensitization to house dust mite ointment. Clinical symptoms, back skin thickness, and transepidermal water loss (TEWL) were monitored weekly, and the immune responses in the auricular lymph nodes were analyzed after necropsy. Results: LS treatment significantly enhanced the secretions of IL-10 and TNFα by DC2.4 cells. IL-8 and TARC production by stimulated HaCaT cells was significantly decreased by co-culturing with LS. Although there were no significant changes in clinical symptoms, skin thickness, or TEWL in the therapeutic setting of the AD mouse model, the number of IgE-positive B cells and IL-4 levels in the local lymph nodes significantly decreased in the LS treatment group. Preventive treatment with LS significantly decreased AD symptoms compared to those in AD control mice. Conclusions: Our findings indicate that the immunomodulatory and anti-inflammatory effects of LS prevent the development of AD. Full article

Reactive oxygen species (ROS) and mitochondrial dysfunction play a major role in skin aging. Due to Tropaeolum majus’ suggested protective actions against ROS, a link between T. majus extract and increased cytoglobin (CYGB) expression was evaluated for cultured skin cells. Human dermal fibroblasts and keratinocytes were treated with 0.5% v/v T. majus extract and the effect of this treatment on the expression of CYGB and on a range of cellular markers of aging were evaluated. In fibroblasts, the treatment with the extract was associated with an increase in CYGB levels. It also decreased ROS concentrations, improved the function of mitochondria, and stimulated the synthesis of collagen and elastin. Moreover, it downregulated a set of genes controlling the terminal differentiation of keratinocytes. T. majus extract activates oxygen transport within natural killer cells and thus enhances their activity, suggesting a potential senolytic effect. This extract seemed to exert a protective effect on various aging pathways such as ROS production, mitochondrial dysfunction, and collagen homeostasis, playing a promising role against skin aging. Full article