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Objective: To evaluate the effects of phenolic acids (caffeic, ferulic, and coumaric acids) and flavones (luteolin and apigenin) on the proliferation and melanogenesis in murine melanoma B16-F10 cells. Methods: Cell proliferation was determined after 24 and 48 hours of incubation using MTT assay. The effects of these tested compounds on cell cycle progression were analyzed by flow cytometry. Moreover, the melanin content and tyrosinase activity were measured spectrophotometrically at 475 nm. Results: Luteolin and apigenin exhibited significant anti-proliferative activity against B16-F10 cells, while caffeic, ferulic, and coumaric acids induced slight inhibition after 24 and 48 hours of incubation. The tested compounds disturbed cell cycle progression of B16-F10, by a subsequent decrease in G
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Objective: To compare the effects of softeners including ethanol, propylene glycol and mixed alcohol (ethanol-propylene glycol 2:8) on the preparation of glabridin ethosomes (GLA-ES), and provide the selection basis of the softeners for studying the ethosomes of insoluble drugs. Methods: GLA-ES were prepared by injection-ultrasonic binding method with ethanol, propylene glycol and mixed alcohol (ethanol-propylene glycol, 2:8) as softeners. The morphology, size, Zeta potential, entrapment efficiency, stability, and in vitro drug release of GLA-ES were investigated. Tyrosinase activity on melanoma B16-OVA cells were detected to evaluate the inhibition of GLA-ES on the synthesis of melanin, the experiment of potassium ferricyanide reducing power was performed to evaluate the antioxidant effect of GLA-ES, and human epidermal HaCaT cells and rat skin were used for preliminary safety evaluation. Results: GLA-ES were yellow translucent liquid, containing vesicular phospholipid bilayer structure, the average particle size of GLA-Et-ES, GLA-PG-ES and GLA-MA-ES were (34.24 ± 0.29), (62.31 ± 1.66) and (41.20 ± 1.13) nm, respectively; The Zeta potential were (-41.0 ± 1.8), (-32.9 ± 0.2) and (-35.8 ± 1.6) mV, the entrapment efficiency were (91.47 ± 2.39)%, (87.33 ± 1.31)% and (91.39 ± 3.59)%, respectively, which had good stability of storage at 4 ℃ for 20 d, in vitro drug release behaviors of GLA-ES fitted Higuchi equation, implying their sustained release properties. Compared with the glabridin suspension, the inhibitory effects of GLA-Et-ES, GLA-PG-ES and GLA-MA-ES on tyrosinase activity in melanoma B16-OVA cells were increased by 38.07%, 19.58% and 40.42%, respectively. The results of potassium ferricyanide reducing power also showed that GLA-ES had a stronger in vitro antioxidant effect than the glabridin suspension; GLA-ES were nearly nontoxic on normal cells and had no irritation to rat skin. Conclusion: GLA-ES can be obtained by hree kinds of softeners, which can inhibit the synthesis of melanin and enhance the antioxidant effect with good safety. The present research will provide the basis for further developing skin-whitening cosmetics or pharmaceutical external preparation. For the insoluble drugs such as glabridin, when mixed alcohol (ethanol-propylene glycol) was selected as the softener to prepare ethosome, it exhibited better encapsulation efficiency and stability than that of ethanol or propylene glycol as the softener alone.
ABSTRACT
The present study observed the effects of a green tea (Camellia sinensis) flower extract (GTFE) on melanin synthesis in B16-F10 melanoma cells. GTFE exhibited antioxidant activity on 2,2-diphenyl-1-picrylhydrazyl and inhibited mushroom tyrosinase activity in a dose-dependent manner. Furthermore, GTFE significantly diminished α-melanocyte stimulating hormone (α-MSH) stimulated cellular melanin content and tyrosinase activity throughout the concentration range evaluated. Based on RNA sequencing analysis, differential gene expression patterns observed in α-MSH stimulated B16-F10 melanoma cells were normalized by the addition of GTFE. In particular, the expression levels of melanoregulin and tyrosinase genes which are key regulating genes in melanin synthesis were up-regulated by 3.5 and 3 fold respectively by α-MSH, and were normalized to control levels by the addition of GTFE. The results suggest that GTFE inhibits melanin synthesis in α-MSH stimulated B16-F10 melanoma cells by normalizing expression of genes that are essential for melanin synthesis. Overall, the results suggest that GTFE could be applied in the development of a whitening agent for the treatment of dermal hyperpigmentation.
Subject(s)
Agaricales , Antioxidants , Flowers , Gene Expression , Hyperpigmentation , Melanins , Melanoma , Monophenol Monooxygenase , Sequence Analysis, RNA , TeaABSTRACT
Ultraviolet (UV) radiation is the main physiological stimulus for human skin pigmentation. Recently, nitric oxide (NO) have been involved in mediation of skin pigmentation induced by UVB. Rutin, a flavonoid of vegetables and fruits, has antiviral and antioxidant properties. Therefore, we investigated the effect of rutin on UVB-induced melano-genesis and NO production in HM3KO cells. In this study, we demonstrated that UVB-irradiation stimulated melanin content and tyrosinase activity in HM3KO cells. Rutin suppressed UVB-stimulated total melanin content and tyrosinase activity in a dose-dependent manner. Additionally, we showed that UVB-irradiation stimulated NO production in HM3KO cells. Rutin also suppressed UVB-induced NO production and repaired reduction of cell proliferation by UVB. UVB stimulation of melanogenesis was mimicked by exogenous NO donor (sodium nitroprusside, SNP), and rutin effectively suppressed it. Therefore, we concluded that rutin suppressed UVB-stimulated melanogenesis and that it is involved in melanogenesis regulation partially through the suppression of UVB-induced NO production.
Subject(s)
Humans , Cell Proliferation , Fruit , Melanins , Melanoma , Monophenol Monooxygenase , Negotiating , Nitric Oxide , Nitroprusside , Rutin , Skin Pigmentation , Tissue Donors , VegetablesABSTRACT
The gene for tyrosinase has been mapped to the long arm of chromosome 11 at 11q14-21. The gene is at least 50Kb in length and its coding region is divided into five exons. Until now several mutations of the tyrosinase gene have been identifed in patient with typical oculocutaneous albinism (OCA) who are responsible for tyrosinase negative OCA. It may be possible to determine the types of OCA by measuring the hairbulb tyrosinase activity. Hairbulb tyrosinase activity was examined in a Korean albino to determine the type of OCA. And also tyrosinase assay was carried out in normally pigmented individuals and all members of a Korean albino's family to examine the tyrosinase activities. Five exons of tyrosinase gene from a Korean albino were amplified by polymerase chain reaction. Each amplified exon segments were independently subcloned and DNA sequences of clones were determined. The results obtained were as follows : 1. A Korean albino had no measurable hairbulb tyrosinase activity and was identified as type IA (tyrosinase negative) oculocutaneous albinism. 2. Normally pigmented individuals had different ranges of hairbulb tyrosinase activity. 3. A Korean albino had two single base insertions within exon V (between 337bp and 338bp, 353bp and 354bp) of tyrosinase gene. These insertional mutations might disrupt tyrosinase function and were associated with a total lack of melanin biosynthesis.
Subject(s)
Humans , Albinism , Albinism, Oculocutaneous , Arm , Base Sequence , Chromosomes, Human, Pair 11 , Clinical Coding , Clone Cells , Exons , Melanins , Monophenol Monooxygenase , Polymerase Chain ReactionABSTRACT
Objective:To study the effects of different molecular weight of collagen polypeptides from Apostichopus japonicus (A1:6 000U