Cytotoxicity In HaCaT Cells Research Articles

Trivalent arsenicals induce skin toxicity through thiol depletion

Arsenic, a widespread environmental contaminant, is highly toxic to human health. Arsenic exposure is associated with the occurrence of skin lesions and diseases. This study investigated the dermal toxicity of trivalent arsenicals (AsIII and MMAIII) and its underlying mechanism using human keratinocyte cell line and ex vivo porcine skin. AsIII and MMAIII induced concentration-dependent cell apoptosis and necrosis in HaCaT cells, which was confirmed in ex vivo porcine skin. AsIII and MMAIII increased reactive oxygen species generation and GSH depletion. Interestingly, radical scavenger antioxidants such as Vitamin C failed to mitigate arsenic-induced cytotoxicity, while thiol-containing compounds effectively alleviated it, suggesting a key role of thiol depletion in the trivalent arsenical-induced dermal toxicity. DMSA showed the strongest protective effects against AsIII and MMAIII-induced cytotoxicity in HaCaT cells. Of note, DMSA restored arsenical-induced tissue damage, and reduced the apoptosis in ex vivo porcine skin, highlighting its potential use to alleviate arsenic-induced skin lesions and diseases.

Enhancing skin delivery of tranexamic acid via esterification: synthesis and evaluation of alkyl ester derivatives.

Tranexamic acid (TA) is widely used clinically as a skin whitening agent for treating melasma and hyperpigmentation. However, oral administration of TA is often associated with adverse effects. Topical application could mitigate these issues, but the hydrophilic nature of TA limits its topical use. To overcome this limitation, we explored the design of TA alkyl ester prodrugs to enhance skin absorption. Our study specifically focused on the butyl and octyl ester derivatives of TA. The results demonstrated that TA4 and TA8 significantly improved skin penetration and deposition, by approximately 2-3 times compared to unmodified TA. Furthermore, these derivatives were rapidly hydrolyzed to release the parent drug within less than 2 h in both skin homogenates and blood. Safety assessments indicated no significant skin irritation in mice and revealed low cytotoxicity in HaCaT cells when exposed to the TA ester derivatives. We also developed a hydrogel formulation incorporating the TA derivatives, using hydroxyethyl cellulose, propylene glycol, Tween 80, and chlorobutanol. This formulation exhibited good skin absorption, stability, and user experience, making it a promising candidate for topical application. To sum up, the alkyl esterification prodrug design provides a promising approach for enhancing the skin delivery of TA.

Derivative of 7-hydroxycoumarin has antifungal potential against Candida species and low cytotoxicity against human cells: In silico studies and biological evaluation

This study investigates the antifungal and cytotoxic properties of 7-(pentyloxy)-2H-chromen-2-one. Through molecular docking and dynamics simulations, we explored the compound's interactions with fungal cell protein targets. Notably, it exhibited strong affinities for 1,3β-glucan synthase, squalene epoxidase, δ-14-sterol reductase, 14-α-demethylase, and thymidylate synthase, with binding energies ranging from -100.39 to -73.15 kcal/mol. Molecular dynamics simulations confirmed its stable binding at active targets. The MIC and MFC values ranged from 67.16 μM (15.6 μg/mL) to 537.28 μM (125.0 μg/mL). The compound displayed promising antifungal effects, inhibiting fungal growth for at least 24 hours. Fungal plasma membrane function alteration likely contributed to these antifungal mechanisms. Additionally, the combination of the compound with nystatin, fluconazole, and caspofungin showed indifferent effects on antifungal activity. Cytotoxicity assessment in human keratinocyte cells (HaCaT) revealed an IC50 of 100 μM, which was approximately 1.5 times higher than the MIC for C. krusei. Thus, the compound exhibited strongly in silico and in vitro antifungal activity with low cytotoxicity in HaCaT cells. These findings support its potential as a candidate for further development as an antifungal compound.

Cannflavins A and B with Anti-Ferroptosis, Anti-Glycation, and Antioxidant Activities Protect Human Keratinocytes in a Cell Death Model with Erastin and Reactive Carbonyl Species.

Precursors of advanced glycation endproducts, namely, reactive carbonyl species (RCSs), are aging biomarkers that contribute to cell death. However, the impact of RCSs on ferroptosis-an iron-dependent form of cell death-in skin cells remains unknown. Herein, we constructed a cellular model (with human keratinocyte; HaCaT cells) to evaluate the cytotoxicity of the combinations of RCSs (including glyoxal; GO and methyglyoxal; MGO) and erastin (a ferroptosis inducer) using bioassays (measuring cellular lipid peroxidation and iron content) and proteomics with sequential window acquisition of all theoretical mass spectra. Additionally, a data-independent acquisition approach was used to characterize RCSs' and erastin's molecular network including genes, canonical pathways, and upstream regulators. Using this model, we evaluated the cytoprotective effects of two dietary flavonoids including cannflavins A and B against RCSs and erastin-induced cytotoxicity in HaCaT cells. Cannflavins A and B (at 0.625 to 20 µM) inhibited ferroptosis by restoring the cell viability (by 56.6-78.6% and 63.8-81.1%) and suppressing cellular lipid peroxidation (by 42.3-70.2% and 28.8-63.6%), respectively. They also alleviated GO + erastin- or MGO + erastin-induced cytotoxicity by 62.2-67.6% and 56.1-69.3%, and 35.6-54.5% and 33.8-62.0%, respectively. Mechanistic studies supported that the cytoprotective effects of cannflavins A and B are associated with their antioxidant activities including free radical scavenging capacity and an inhibitory effect on glycation. This is the first study showing that cannflavins A and B protect human keratinocytes from RCSs + erastin-induced cytotoxicity, which supports their potential applications as dietary interventions for aging-related skin conditions.

The aryl hydrocarbon receptor (AhR) activation mediates benzo(a)pyrene-induced overexpression of AQP3 and Notch1 in HaCaT cells.

The aim of this study was twofold: (1) evaluate the effect of benzo[a]pyrene (BaP) on expression levels of AQP3 and Notch1 genes in HaCaT cells exposed "in vitro" and (2) investigate the possible biological role of assessed genes by bioinformatics methods. Cells were exposed to increasing concentrations of BaP (0.0-4.0 μM) for 1-4 days. After treatments, cell viability and expression levels of AhR, CYP1A1, AQP3, and Notch1 genes were evaluated. The possible biological role of assessed genes was evaluated using bioinformatics tools. Low cytotoxicity in HaCaT cells dosed with BaP was detected. A significant overexpression (p < .05) of CYP1A1, AQP3, and Notch1 was found in exposed HaCaT cells. The gene expression upregulation was dependent on AhR activation. The bioinformatics analysis showed that these genes were enriched in related cancer signaling pathways. The findings suggest that AQP3 and Notch1 are upregulated by AhR activation in HaCaT cells exposed to BaP.

New Insights into the Dermocosmetic Potential of the Red Seaweed Gelidium corneum.

This work addresses the potential of the red seaweed Gelidium corneum as a source of bioactive ingredients for skin health and wellness in response to the growing awareness regarding the significance of sustainable strategies in developing new nature-based dermocosmetic products. Hydroalcoholic extracts from the dried biomass were subjected to sequential liquid-liquid partitions, affording five different fractions (F1-F5). Their cosmetic potential was assessed through a set of in vitro assays concerning their antioxidant, photoprotective, and healing properties. Additionally, their cytotoxicity in HaCaT cells and their capacity to induce inflammation in RAW 264.7 cells were also evaluated. As a proof-of-concept, O/W emulsions were prepared, and emulsion stability was assessed by optical microscopy, droplet size analysis, centrifugation tests, and rheology analysis. Furthermore, in vivo tests were conducted with the final formulation to assess its antioxidant capacity. At subtoxic concentrations, the most lipophilic fraction has provided photoprotection against UV light-induced photooxidation in HaCaT cells. This was conducted together with the aqueous fraction, which also displayed healing capacities. Regarding the physical and stability assays, the best performance was achieved with the formulation containing 1% aqueous extract, which exhibited water retention and antioxidant properties in the in vivo assay. In summary, Gelidium corneum displayed itself as a potential source of bioactive ingredients with multitarget properties for dermatological use.

Hydrangea serrata Hot Water Extract and Its Major Ingredient Hydrangenol Improve Skin Moisturization and Wrinkle Conditions via AP-1 and Akt/PI3K Pathway Upregulation.

Hydrangea serrata is a plant grown in Korea and Japan with a particular natural compound, hydrangenol. H. serrata has been researched for its anti-fungal properties, and ability to attenuate allergies and promote muscle growth. Its ability to reduce skin dryness is poorly understood. For that reason, we investigated whether H. serrata hot water extracts (Hs-WE) can moisturize keratinocytes. In clinical studies (Approval Code: GIRB-21929-NY and approval Date: 5 October 2021), skin wrinkles and skin moisturizing levels were improved in subjects applying 0.5% Hs-WE compared to the placebo group. We confirmed the components of Hs-WE from the LC/MS-MS analysis. Hs-WE and hydrangenol did not show cytotoxicity in HaCaT cells at all concentrations. Cell growth was also promoted by Hs-WE (5-20 µg/mL) and hydrangenol (15-60 µM) in a wound healing assay. Skin moisturizing factors were upregulated by the presence of Hs-WE or hydrangenol, and the hyaluronidases (HYAL) were inhibited at the mRNA level. Meanwhile, COL1A1 was increased by the presence of Hs-WE or hydrangenol. MAPK, AP-1, and Akt/PI3k signaling proteins, which are associated with cell proliferation and moisturizing factors, were increased by the administration of Hs-WE and hydrangenol. Has-1, 2, and 3 levels were enhanced via JNK when using the inhibitors of MAPK proteins and Hs-WE and hydrangenol, respectively. Taken together, Hs-WE could be used as cosmeceutical materials for improving skin conditions.

Peptide-Protected Gold Nanoclusters Efficiently Ameliorate Acute Contact Dermatitis and Psoriasis via Repressing the TNF-α/NF-κB/IL-17A Axis in Keratinocytes

Immune-mediated skin diseases have a high prevalence and seriously affect patients' quality of life. Gold compounds have been considered promising therapeutic agents in dermatology, but the high incidence of adverse reactions have limited their clinical application. There is a great need to develop more effective and less toxic gold-based drugs. Gold nanoclusters fabricated by using peptides (pep-AuNCs) have appeared as potential biomedical nanomaterials because of their excellent biocompatibility, ease of fabrication and unique physicochemical properties. Glutathione (GSH) is an endogenous tripeptide and has been used for lightening the skin color. Therefore, we fabricated a well-defined gold nanocluster with GSH as an example to explore the immunomodulatory effect of AuNCs on a TNF-α-treated human keratinocyte cell line (HaCaT) in vitro, the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced irritant contact dermatitis (ICD) model and the oxazolone (OXA)-induced psoriatic model in vivo. The results indicated that topically applied AuNCs successfully attenuated the severity of ICD and psoriasis-like lesions. In vitro and in vivo, AuNCs effectively inhibited the abnormal activation of the NF-κB pathway and the consequent overexpression of proinflammatory cytokines in keratinocytes. In particular, the transactivation of IL-17A, the most important cytokine in psoriasis pathology, was effectively inhibited by AuNCs treatment. In addition, AuNCs did not show any obvious cytotoxicity in HaCaT cells at doses even up to 100 µM and did not induce any irritation in the healthy skin and major organs, which indicated their favorable biosafety. These results indicate that biocompatible pep-AuNCs might be a promising gold-based nanomedicine for the treatment of inflammatory skin diseases.

Ultrasound stimulated production of exopolysaccharide with anti-UV radiation activity by increasing cell permeability of Paenibacillus polymyxa

Exopolysaccharide (EPS) produced by Paenibacillus polymyxa PYQ1 may be a promising agent used in the cosmetic field for skin care because of its protective benefits against short-wave ultraviolet (UVC, 100–280 nm) radiation, which induces cytotoxicity in HaCaT cells. We attempted to use low-intensity ultrasound to enhance its fermentation, and the yield of EPS increased by 24 % under the optimum ultrasonic treatment (90 W, 45 s in 9 h). Results of further experiments show that low-intensity ultrasound will kill a few bacterial cells. Therefore, the remaining bacterial cells have more space and more nutrients, growing faster and producing EPS more efficiently. The recoverable physical damage caused by ultrasound increased the cell permeability, and for the first time, we found that low-intensity ultrasound up-regulated the expression of membrane transporters involved with the transport of sucrose and polysaccharides. Owing to these changes, the utilization of carbon sources was accelerated, and the transport of EPS was promoted to the outside of bacterial cells such that the production of EPS was enhanced.

Cherry fruit anthocyanins cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside protect against blue light-induced cytotoxicity in HaCaT cells

Blue light derived from multiple sources, including sunlight, generates reactive oxygen species (ROS) and negatively affects the skin in a manner similar to that of ultraviolet light. Cyanidin-3-O-glucoside (C3OG) and cyanidin-3-O-rutinoside (C3OR) are anthocyanin antioxidants that have protective effects on various tissues and cell types. However, the effects of anthocyanins on blue light-mediated changes remain unconfirmed. In this study, we determined the protective effects of C3OG and C3OR isolated and purified from waste cherry fruits (Prunus serrulata L. var. tomentella Nakai) against the blue light-induced ROS formation and inflammatory responses in HaCaT cells. It is showed that the treatment of C3OG and C3OR significantly reduced the blue light-induced cytotoxicity and ROS production in a dose dependent manner. Furthermore, we found that focal adhesion kinase (FAK) is a major upstream of blue light-induced expression of inflammatory cytokines (TNF-α, IL-6 and IL-8), and these effects were attenuated by C3OG or C3OR treatment. In the initial reaction, blue lights increased the phosphorylation of inhibitory-κB Kinase α (IKKα), c-jun N-terminal kinase (JNK), and p38. The phosphorylation of these intracellular proteins was reduced via FAK inhibitor, NAC (ROS scavenger), and anthocyanin treatments. After 24 h of blue light irradiation, C3OG or C3OR treatment markedly inhibited caspase-3-mediated apoptosis and cleaved-FAK-mediated anoikis, which is cell detachment-induced apoptosis. Therefore, our results indicate that C3OG and C3OR effectively protected human keratinocytes from harmful blue light-induced cytotoxicity and inflammation.

CHAC1 exacerbates arsenite cytotoxicity by lowering intracellular glutathione levels.

We here examined whether CHAC1 is implicated in arsenite (As(III))-induced cytotoxicity in HaCaT cells. We found that HaCaT cells in which the intracellular GSH levels were elevated by transfection with CHAC1 siRNA showed decreased sensitivity to As(III) compared to the control cells. Treatment with BSO (an inhibitor of GSH biosynthesis) abolished the decrease in sensitivity to As(III), suggesting that an increase in intracellular GSH levels was involved in the decrease in sensitivity to As(III) due to the decrease in the levels of CHAC1 expression. When we examined the expression of CHAC1 after exposure of HaCaT cells to As(III), the levels of CHAC1 were increased. Since CHAC1 is a proapoptotic factor, we examined appearance of apoptotic cells and cleavage of caspase-3 after exposure to As(III) to determine whether As(III)-induced CHAC1 up-regulation was involved in apoptosis induction. The results showed that induction of apoptosis by As(III) exposure was not detected in CHAC1 siRNA-transfected cells. Together, our findings indicate that CHAC1 is involved in the sensitivity of HaCaT cells to As(III) by regulating the intracellular GSH levels, and in particular, CHAC1 is involved in As(III)-induced apoptosis.

Photoprotective properties of myconoside, isolated from Haberlea rhodopensis, under UVA/UVB-induced cytotoxicity in HaCaT cells

Photoprotective properties of myconoside, isolated from Haberlea rhodopensis, under UVA/UVB-induced cytotoxicity in HaCaT cells

Hibiscus sabdariffa Extract Protects HaCaT Cells against Phenanthrene-Induced Toxicity through the Regulation of Constitutive Androstane Receptor/Pregnane X Receptor Pathway.

Phenanthrene (Phe) exposure is associated with skin ageing, cardiotoxicity and developmental defects. Here, we investigated the mode of Phe toxicity in human keratinocytes (HaCaT cells) and the attenuation of toxicity on pre-treatment (6 h) with ethanol extract of Hibiscus sabdariffa calyxes (HS). Cell viability, reactive oxygen species (ROS) generation, mitochondrial membrane potential (ΔΨm) alteration, changes in the transcriptional activity of selected genes involved in phase I and II metabolism, antioxidant response and gluconeogenesis, western blot and docking studies were performed to determine the protective effect of HS against Phe. Phe (250 μM) induced cytotoxicity in HaCaT cells through AhR-independent, CAR/PXR/RXR-mediated activation of CYP1A1 and the subsequent alterations in phase I and II metabolism genes. Further, CYP1A1 activation by Phe induced ROS generation, reduced ΔΨm and modulated antioxidant response, phase II metabolism and gluconeogenesis-related gene expression. However, pre-treatment with HS extract restored the pathological changes observed upon Phe exposure through CYP1A1 inhibition. Docking studies showed the site-specific activation of PXR and CAR by Phe and inhibition of CYP1A1 and CYP3A4 by the bioactive compounds of HS similar to that of the positive controls tested. Our results conclude that HS extract can attenuate Phe-induced toxicity in HaCaT cells through CAR/PXR/RXR mediated inhibition of CYP1A1.

Dermal bioaccessibility and cytotoxicity of heavy metals in urban soils from a typical plateau city: Implication for human health

The dermal exposure of heavy metals in contaminated urban soils poses huge environmental health risks globally. However, their dermal bioaccessibility and adverse effects on human skin cells were not fully understood. In this study, we measured the total and dermal bioaccessibility of Cr, As, Cd, Pb, and Cu in four selected urban soil samples from Kunming, Yunnan, China, and evaluated the cellular responses of these bioaccessible extracts on human keratinocytes (HaCaT). Among all the metals, only As in Soil-3 (S3) exceeded Chinese risk screening and Yunnan background values at 38.2 mg/kg. The average concentrations of Cr, As, Cd, Pb, and Cu in all soil samples were 47.79, 15.50, 3.11, 104.27, and 180.29 mg/kg respectively. Although relatively high concentrations of heavy metals were detected in soil samples, the highest dermal bioaccessibility of Cd was 3.57% with others' being lower than 1%. The bioaccessible dermal-absorbed doses (DADs) of Cr, As, Cd, Pb, and Cu from soils reflected acceptable health risks since all DADs were below the corresponding derived dermal reference values. However, the toxic data showed the extracts of S3 and S4 presented certain cytotoxicity in HaCaT cells, indicating the existing models based on dermal bioaccessibility and DADs may be not accurate enough to assess their human health risk. Taken together, the human health risk assessment should be modified by taking their skin cytotoxicity into account.

Electrospun Biomimetic Multifunctional Nanofibers Loaded with Ferulic Acid for Enhanced Antimicrobial and Wound-Healing Activities in STZ-Induced Diabetic Rats.

Diabetic foot ulceration is the most distressing complication of diabetes having no standard therapy. Nanofibers are an emerging and versatile nanotechnology-based drug-delivery system with unique wound-healing properties. This study aimed to prepare and evaluate silk-sericin based hybrid nanofibrous mats for diabetic foot ulcer. The nanofibrous mats were prepared by electrospinning using silk sericin mixed with different proportions of polycaprolactone (PCL) and cellulose acetate (CA) loaded with ferulic acid (FA). The in vitro characterizations, such as surface morphology, mechanical properties, swelling behavior, biodegradability, scanning electron microscopy, and drug release were carried out. The SEM images indicated that nanofibers formed with varied diameters, ranging from 100 to 250 nm, and their tensile strength was found to range from 7 to 15 MPa. In vitro release demonstrated that the nanofibers sustained FA release over an extended time of period. In vitro cytotoxicity showed that the nanofibers possessed a lower cytotoxicity in HaCaT cells. The in vivo wound-healing studies demonstrated an excellent wound-healing efficiency of the nanofibers in diabetic rats. Furthermore, the histopathological studies showed the nanofibers’ ability to restore the skin’s normal structure. Therefore, it was concluded that the prepared silk-sericin-based hybrid nanofibers loaded with FA could be a promising drug-delivery platform for the effective treatment of diabetic foot ulcers.

Safety Assessment of Cuticle Remover Cosmetics In Vivo and In Vitro

Recently, the issue of the harmful effects of nail care products has been posed. In case of cuticle remover, information on hazards of chemical substances is limited and product safety reports are also insufficient. This study evaluated the safety of the top three commercially selling cuticle removers that are widely used in nail care: Blue cross, Zero cleanser and Flower vita cuticle cares. To measure the pH level of cuticle remover cosmetics, distilled water and DMEM. The toxic effect of cuticle removers on cultured HaCaT was identified by MTT-assay. The patch test was performed to evaluate the occurrence of erythema on the patch area according to the criteria of ICDRG after applying the cuticle remover cosmetics (as is). Adherence to the cosmetic pH measurement guidelines, it w as confirmed that the blue cross product did not meet the pH standard of the final product of the domestic cosmetic method. When measuring the pH by diluting DMEM with a solvent, Flower vita product maintained a pH close to Neutral 7.0 overall. All three cuticle removers demonstrated dose-dependent cytotoxic on HaCaT cell. The viability of cells treated with 10 μg/mL Blue cross or 10 μg/mL Zero cleanser was presented below 10%. Otherwise, Flower vita treatment at concentrations of 0.5~20 μg up to 20 μg/mL did not affect the viability (above 70%) in the HaCaT. Of the patch test, there was positive in one case (3.3%) at 2 weeks. It was observed that a doubful reaction (-/+) to Flower vita and weak positive reactions (+) to Blue cross, and zero cleanser. Taken together, it was shown that the Flower vita product have the lowest cytotoxicity in HaCaT cells and slight allergic reaction, proving more safer than other tw o products &lt;i&gt;in vivo&lt;/i&gt; and &lt;i&gt;in vitro&lt;/i&gt;.

Transdermal Delivery of Lidocaine-Loaded Elastic Nano-Liposomes with Microneedle Array Pretreatment

This study aimed to improve the transdermal delivery of lidocaine hydrochloride (LidH) using elastic nano-liposomes (ENLs) and microneedle (MN) array pretreatment. LidH-containing ENLs were prepared using soybean phosphatidylcholine and cholesterol, with Span 80 or Tween 80, using a reverse-phase evaporation method. The ENL particle size, stability, and encapsulation efficiency (EE) were characterized and optimized based on the component ratio, pH, and type of surfactant used. In vitro transdermal diffusion study was performed on MN-pretreated mouse skin using Franz diffusion cells. The anesthetic effects of LidH in various formulations after dermal application were evaluated in vivo in rats by measuring the tail withdrawal latency after photothermic stimulation. Stable LidH-loaded Tween 80 or Span 80 ENLs were obtained with particle sizes of 115.8 and 146.6 nm and EEs of 27% and 20%, respectively. The formulations did not exert any cytotoxicity in HaCaT cells. Tween 80 and Span 80 ENL formulations showed enhanced LidH delivery on pretreated mice skin in vitro and prolonged the anesthetic effect in vivo compared to that by LidH application alone. LidH-loaded ENLs applied to MN-pretreated skin can shorten the onset time and prolong the anesthetic effect safely, which merits their further optimization and practical application.

Uptake, intracellular dissolution, and cytotoxicity of silver nanowires in cell models

The uptake, intracellular dissolution, and cytotoxicity of silver nanowires (AgNWs) in two cell models (human keratinocytes - HaCaT cells and murine macrophages) were systemically investigated for the first time. Cellular uptake of AgNWs occurred mainly via pathways of clathrin-dependent endocytosis, caveolae-dependent endocytosis, and phagocytosis. AgNWs could be internalized by two types of cells with numerous lysosomal vesicles detected in close vicinity to AgNWs. Meanwhile, AgNWs exposure caused lysosomal permeabilization and release of cathepsisn B into cytoplasm. Furthermore, for the first time, this study found that AgNWs exposure inhibited the transmembrane ATP binding cassette (ABC) efflux transporter activity, which could make AgNWs as chemosensitizers to increase the toxicity of other xenobiotic pollutants. Toxicity assays evaluating reactive oxygen species production and mitochondrial activity indicated that cytotoxicity differed for different cell types and particles. The intracellular presence of AgNWs with different diameters induced similar toxic events but to different extents. AgNWs were absorbed by macrophages more efficiently than HaCaT cells, while AgNWs exhibited only marginal cytotoxicity towards macrophages compared to HaCaT cells. Using an Ag+ fluorescence probe, it was found that a fraction of AgNWs was dissolved inside the lysosomes. A higher amount of released Ag+ was detected in HaCaT cells than in macrophages, which might partially contribute to their higher cytotoxicity in HaCaT cells. The toxicity of AgNWs in HaCaT cells and macrophages is due to the high-aspect nature of the nanowires rather than the extracellular release of Ag+. This study may be useful for risk assessments of AgNWs in their practical applications in the biomedical field.

Isolation of Valuable Bioactive Compounds from Aerial Parts of Black Wattle, a Forest Solid Waste

This study aimed at obtaining an extract enriched in phenolic compounds from the aerial parts of black wattle waste (Acacia mearnsii De Wild), characterization of its composition, and investigation of its antioxidant potential and preclinical toxicological profile. First, a phenolic compound enriched extract (PCEE) was obtained by sequential fractionation. Thereafter, the main classes of secondary metabolites present in PCEE were identified and quantified. The antioxidant, cytotoxic, and cytogenotoxic activities were evaluated using in vitro assays. Toxicological effects on locomotor function were assessed using in vivo open field and plus maze models. Cinnamic acid and coumarin were isolated from the PCEE and identified. In addition, high contents of phenolic compounds and flavonoids, responsible for the promising antioxidant activity, were quantified. The extract should a dose-dependent in vitro cytotoxicity in HaCaT cells. In the cytogenotoxicity bioassay, no differences in the mitotic index and micronuclei frequency were observed between PCEE and negative control groups. Also, there were no significant effects of the extract on the motor function. Taken together, these results show that the aerial parts of A. mearnsii can be used for obtaining bioactive compounds with the potential for promoting human and animal health.

Regulation of Anti-Oxidative, Anti-Inflammatory, and Anti-Apoptotic Activity of Advanced Cooling Composition (ACC) in UVB-Irradiated Human HaCaT Keratinocytes.

We recently demonstrated that advanced cooling composition (ACC) has effective ingredients that exhibit anti-inflammatory effects in RAW 264.7 cells stimulated with lipopolysaccharide (LPS) and exhibit strong antimicrobial effects on Pseudomonas aeruginosa, Staphylococcus aureus, MRSA (methicillin-resistant Staphylococcus aureus), Candida albicans, and Streptococcus mutans. To further investigate whether ACC has beneficial effects in ultraviolet B (UVB)-irradiated human keratinocytes (HaCaT cells), HaCaT cells were pretreated with ACC prior to UVB irradiation. Our data showed that ACC, which is effective at 100 µg/mL, is nontoxic and has an antioxidative effect against UVB-induced intracellular reactive oxygen species (ROS) in HaCaT cells. In addition, ACC exerts cytoprotective effects against UVB-induced cytotoxicity in HaCaT cells by inhibiting abnormal inflammation and apoptosis through the regulation of mitogen-activated protein kinase (MAPK) signals, such as jun-amino-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK). Therefore, these results indicate that ACC is a potentially beneficial raw material that possesses antioxidative, anti-inflammatory, and antiapoptotic effects against UVB-induced keratinocytes and may have applications in skin health.