Action mechanism of anti-wrinkle effect of Rhamnus yoshinoi methanol extract in human dermal fibroblast and keratinocyte cell lines

Emissions from modern engines induce distinct effects in human olfactory mucosa cells, depending on fuel and aftertreatment

Ultrafine particles (UFP) with a diameter of ≤0.1 μm, are contributors to ambient air pollution and derived mainly from traffic emissions, yet their health effects remain poorly characterized. The olfactory mucosa (OM) is located at the rooftop of the nasal cavity and directly exposed to both the environment and the brain. Mounting evidence suggests that pollutant particles affect the brain through the olfactory tract, however, the exact cellular mechanisms of how the OM responds to air pollutants remain poorly known. Here we show that the responses of primary human OM cells are altered upon exposure to UFPs and that different fuels and engines elicit different adverse effects. We used UFPs collected from exhausts of a heavy-duty-engine run with renewable diesel (A0) and fossil diesel (A20), and from a modern diesel vehicle run with renewable diesel (Euro6) and compared their health effects on the OM cells by assessing cellular processes on the functional and transcriptomic levels. Quantification revealed all samples as UFPs with the majority of particles being ≤0.1 μm by an aerodynamic diameter. Exposure to A0 and A20 induced substantial alterations in processes associated with inflammatory response, xenobiotic metabolism, olfactory signaling, and epithelial integrity. Euro6 caused only negligible changes, demonstrating the efficacy of aftertreatment devices. Furthermore, when compared to A20, A0 elicited less pronounced effects on OM cells, suggesting renewable diesel induces less adverse effects in OM cells. Prior studies and these results suggest that PAHs may disturb the inflammatory process and xenobiotic metabolism in the OM and that UFPs might mediate harmful effects on the brain through the olfactory route. This study provides important information on the adverse effects of UFPs in a human-based in vitro model, therefore providing new insight to form the basis for mitigation and preventive actions against the possible toxicological impairments caused by UFP exposure.

Combined Toxicological Effects of Di (2-Ethylhexyl) Phthalate and UV-B Irradiation through Endoplasmic Reticulum Stress-Tight Junction Disruption in Human HaCaT Keratinocytes

Di (2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer, and human exposure to DEHP is widespread and frequent. However, information about the combined effect of DEHP and ultraviolet (UV)-B on the skin are still limited. We investigated the cytotoxic effects of DEHP and UV-B on HaCaT keratinocytes and evaluated the related underlying mechanisms involving endoplasmic reticulum (ER) stress signals and the disruption of junction complexes as an effective target for skin inflammation. Our results revealed that co-treatment with DEHP and UV-B irradiation alleviated the cell cytotoxicity and markedly decreased X-box binding protein 1 (XBP1), endoplasmic reticulum oxidoreductase 1 alpha (Ero1α), and C/EBP homologous protein (CHOP) whereas a single dose of 40 mJ/cm² UV-B generated mild ER stress to slightly less or similar levels as that seen with DEHP. DEHP was also shown to inhibit tight junctions (TJs) after UV-B irradiation, increased apoptosis by altering apoptotic gene Bax and stress kinases, JNK, and p38 MAPK. Furthermore, exposure of HaCaT cells to DEHP and UV-B irradiation resulted in the marked suppression of the nuclear factor kappa B (NF-κB)/p65 signaling pathway. Taken together, our data suggest that nontoxic DEHP and UV-B irradiation regulated ER stress and epidermal TJ disruption with the induction of apoptosis activation and the secretion of proinflammatory cytokines such as interleukin 1 beta (IL-1β) and IL-6 in human keratinocytes. Further investigation is needed to confirm the mechanisms implicated in its toxicity and determine the effects of exposure to DEHP and UV-B irradiation on markers involved in this study.

Skin-Whitening and Antiwrinkle Proprieties of Maackia amurensis Methanolic Extract Lead Compounds

(1) Background: This study aimed to investigate the feasibility of using Maackia amurensis branch extract as a cosmetic ingredient with skin-whitening and antiwrinkle effects. (2) Methods: The skin-whitening effect of M. amurensis branch extract was confirmed by investigating α-melanocyte-stimulating hormone (α-MSH)-induced melanin synthesis and melanogenic protein expression in B16F1 cells. The antiwrinkle effect of M. amurensis branch extract was verified by assessing matrix metalloproteinase (MMP)-1 expression and soluble collagen content in CCD-986sk cells. The major compounds in M. amurensis branch extract were identified through isolation and characterization and confirmed by high-performance liquid chromatography analysis. (3) Results: M. amurensis branch extract significantly inhibited α-MSH-induced melanin synthesis by 49%, 42%, and 18% at 50, 37.5, and 25 μg/mL concentrations, respectively, compared with the negative control (NC). M. amurensis branch extract also significantly reduced the expression of the microphthalmia-associated transcription factor, tyrosinase-related protein (TRP)-1, TRP-2, and tyrosinase in B16F1 cells. Furthermore, M. amurensis branch extracts decreased ultraviolet A-induced MMP-1 expression and increased soluble collagen synthesis in CCD-986sk cells. In addition, the major compounds present in M. amurensis branch extract were found to be formononetin, genistein, trans-resveratrol, piceatannol, and tectoridin. (4) Conclusions: M. amurensis branch extract has skin-whitening and antiwrinkle properties. Therefore, it can be used as an ingredient in functional cosmetics with skin-whitening and antiwrinkle effects.

Anti-Inflammatory Effect of Auranofin on Palmitic Acid and LPS-Induced Inflammatory Response by Modulating TLR4 and NOX4-Mediated NF-κB Signaling Pathway in RAW264.7 Macrophages

Chronic inflammation, which is promoted by the production and secretion of inflammatory mediators and cytokines in activated macrophages, is responsible for the development of many diseases. Auranofin is a Food and Drug Administration-approved gold-based compound for the treatment of rheumatoid arthritis, and evidence suggests that auranofin could be a potential therapeutic agent for inflammation. In this study, to demonstrate the inhibitory effect of auranofin on chronic inflammation, a saturated fatty acid, palmitic acid (PA), and a low concentration of lipopolysaccharide (LPS) were used to activate RAW264.7 macrophages. The results show that PA amplified LPS signals to produce nitric oxide (NO) and various cytokines. However, auranofin significantly inhibited the levels of NO, monocyte chemoattractant protein-1, and pro-inflammatory cytokines, such as interleukin (IL)-1β, tumor necrosis factor-α, and IL-6, which had been increased by co-treatment with PA and LPS. Moreover, the expression of inducible NO synthase, IL-1β, and IL-6 mRNA and protein levels increased by PA and LPS were reduced by auranofin. In particular, the upregulation of NADPH oxidase (NOX) 4 and the translocation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) induced by PA and LPS were suppressed by auranofin. The binding between the toll-like receptor (TLR) 4 and auranofin was also predicted, and the release of NO and cytokines was reduced more by simultaneous treatment with auranofin and TLR4 inhibitor than by auranofin alone. In conclusion, all these findings suggested that auranofin had anti-inflammatory effects in PA and LPS-induced macrophages by interacting with TLR4 and downregulating the NOX4-mediated NF-κB signaling pathway.

Phloroglucinol Attenuates Ultraviolet B-Induced 8-Oxoguanine Formation in Human HaCaT Keratinocytes through Akt and Erk-Mediated Nrf2/Ogg1 Signaling Pathways

Ultraviolet B (UVB) radiation causes DNA base modifications. One of these changes leads to the generation of 8-oxoguanine (8-oxoG) due to oxidative stress. In human skin, this modification may induce sunburn, inflammation, and aging and may ultimately result in cancer. We investigated whether phloroglucinol (1,3,5-trihydroxybenzene), by enhancing the expression and activity of 8-oxoG DNA glycosylase 1 (Ogg1), had an effect on the capacity of UVB-exposed human HaCaT keratinocytes to repair oxidative DNA damage. Here, the effects of phloroglucinol were investigated using a luciferase activity assay, reverse transcription-polymerase chain reactions, western blot analysis, and a chromatin immunoprecipitation assay. Phloroglucinol restored Ogg1 activity and decreased the formation of 8-oxoG in UVB-exposed cells. Moreover, phloroglucinol increased Ogg1 transcription and protein expression, counteracting the UVB-induced reduction in Ogg1 levels. Phloroglucinol also enhanced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) as well as Nrf2 binding to an antioxidant response element located in the Ogg1 gene promoter. UVB exposure inhibited the phosphorylation of protein kinase B (PKB or Akt) and extracellular signal-regulated kinase (Erk), two major enzymes involved in cell protection against oxidative stress, regulating the activity of Nrf2. Akt and Erk phosphorylation was restored by phloroglucinol in the UVB-exposed keratinocytes. These results indicated that phloroglucinol attenuated UVB-induced 8-oxoG formation in keratinocytes via an Akt/Erk-dependent, Nrf2/Ogg1-mediated signaling pathway.

Effects of anti-wrinkle and skin-whitening fermented black ginseng on human subjects and underlying mechanism of action

The aim of this study was to determine the effects of anti-wrinkle and skin-whitening of fermented black ginseng (FBG) in human subjects and to examine underlying biochemical mechanisms of action. A clinical study was performed to evaluate efficacy and safety using a 1% FBG cream formulation. Twenty-three subjects were recruited and instructed to apply control or FBG creams each on half of their face twice daily for 8 weeks. After 8 weeks FBG cream significantly reduced appearance of eye wrinkles compared to prior to exposure and control cream. Skin color was significantly brightened using FBG cream in comparison with control cream. To determine the mechanism of actions involved in anti-wrinkle and skin-whitening effects various concentrations of FBG were applied to human fibroblast CCD-986sk and mouse melanoma B16F1 cells. Collagen synthesis in CCD-986sk cells was improved significantly at 1, 3, 10, or 30 µg/ml of FBG. At 30 µg/ml, FBG significantly inhibited (73%) collagenase, and matrix metalloproteinase-1 (MMP-1) compared to control. Tyrosinase activity and DOPA (3,4-dihydroxy-L-phenylalanine) oxidation were significantly decreased at all tested concentrations. Melanin production in B16F1 cells was concentration-dependently reduced 15% to 60% by all concentrations of FBG. These results suggested that a 1% FBG cream exerted anti-wrinkle and skin-whitening effects.

Effects of anti-wrinkle and skin-whitening fermented black ginseng on human subjects and underlying mechanism of action

The aim of this study was to determine the effects of anti-wrinkle and skin-whitening of fermented black ginseng (FBG) in human subjects and to examine underlying biochemical mechanisms of action. A clinical study was performed to evaluate efficacy and safety using a 1% FBG cream formulation. Twenty-three subjects were recruited and instructed to apply control or FBG creams each on half of their face twice daily for 8 weeks. After 8 weeks, FBG cream significantly reduced the appearance of eye wrinkles compared to prior to exposure and control cream. Skin color was significantly brightened using FBG cream in comparison with a control cream. To determine the mechanism of actions involved in anti-wrinkle and skin-whitening effects various concentrations of FBG were applied to human fibroblast CCD-986sk and mouse melanoma B16F1 cells. Collagen synthesis in CCD-986sk cells was improved significantly at 1, 3, 10, or 30 µg/ml of FBG. At 30 µg/ml, FBG significantly inhibited (73%) collagenase, and matrix metalloproteinase-1 (MMP-1) compared to control. Tyrosinase activity and DOPA (3,4-dihydroxy-L-phenylalanine) oxidation were significantly decreased at all tested concentrations. Melanin production in B16F1 cells was concentration-dependently reduced from 15% to 60% by all concentrations of FBG. These results suggested that a 1% FBG cream exerted anti-wrinkle and skin-whitening effects.