Selective Cytotoxicity of Hydroquinone for Melanocyte-Derived Cells is Mediated by Tyrosinase Activity but Independent of Melanin Content

1988 ◽  
Vol 1 (6) ◽  
pp. 386-389 ◽  
Author(s):  
CHRISTOPHER J. SMITH ◽  
KATHYRN B. O'HARE ◽  
JOHN C. ALLEN
2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Huey-Chun Huang ◽  
Hsiao-Fen Wang ◽  
Kuang-Hway Yih ◽  
Long-Zen Chang ◽  
Tsong-Min Chang

The antimelanogenic and antioxidant activities of the essential oil extracted from the leaves ofAcorus macrospadiceus(Yamamoto) F. N. Wei et Y. K. Li have never been explored. The essential oil effectively inhibited mushroom tyrosinase activity (EC50= 1.57 mg/mL) and B16F10 tyrosinase activity (IC50= 1.01 mg/mL), decreased the melanin content (EC50= 1.04 mg/mL), and depleted the cellular level of the reactive oxygen species (ROS) (EC50= 1.87 mg/mL). The essential oil effectively scavenged 2,2-diphenyl-1-picryl-hydrazyl (DPPH) (EC50= 0.121 mg/mL) and 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) ABTS+radicals (EC50= 0.122 mg/mL). It also exhibited an apparent reducing power (EC50= 0.021 mg/mL) and metal-ion chelating activity (EC50= 0.029 mg/mL). The chemical constituents of the essential oil are ethers (55.73%), ketones (19.57%), monoterpenes (7.82%), alcohols (3.85%), esters (3.77%), sesquiterpenes (3.72%), and aromatic compounds (2.85%). The results confirm thatA. macrospadiceusessential oil is a natural antioxidant and inhibitor of melanogenesis.


Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3403
Author(s):  
Nurshafika Mohd Sakeh ◽  
Nurliyana Najwa Md Razip ◽  
Farah Idayu Mohd Ma’in ◽  
Mohammad Nazri Abdul Bahari ◽  
Naimah Latif ◽  
...  

Excessive production of melanin implicates hyperpigmentation disorders. Flavokawain A (FLA) and flavokawain B (FLB) have been reported with anti-melanogenic activity, but their melanogenic inhibition and toxicity effects on the vertebrate model of zebrafish are still unknown. In the present study, cytotoxic as well as melanogenic effects of FLA and FLB on cellular melanin content and tyrosinase activity were evaluated in α-MSH-induced B16/F10 cells. Master regulator of microphthalmia-associated transcription factor (Mitf) and the other downstream melanogenic-related genes were verified via quantitative real time PCR (qPCR). Toxicity assessment and melanogenesis inhibition on zebrafish model was further observed. FLA and FLB significantly reduced the specific cellular melanin content by 4.3-fold and 9.6-fold decrement, respectively in α-MSH-induced B16/F10 cells. Concomitantly, FLA significantly reduced the specific cellular tyrosinase activity by 7-fold whilst FLB by 9-fold. The decrement of melanin production and tyrosinase activity were correlated with the mRNA suppression of Mitf which in turn down-regulate Tyr, Trp-1 and Trp-2. FLA and FLB exhibited non-toxic effects on the zebrafish model at 25 and 6.25 µM, respectively. Further experiments on the zebrafish model demonstrated successful phenotype-based depigmenting activity of FLA and FLB under induced melanogenesis. To sum up, our findings provide an important first key step for both of the chalcone derivatives to be further studied and developed as potent depigmenting agents.


Homeopathy ◽  
2019 ◽  
Vol 108 (03) ◽  
pp. 183-187 ◽  
Author(s):  
Renuka Munshi ◽  
Samidha Joshi ◽  
Gitanjali Talele ◽  
Rajesh Shah

Introduction The authors had previously conducted an in-vitro study to observe the effect of homeopathic medicines on melanogenesis, demonstrating anti-vitiligo potential by increasing the melanin content in murine B16F10 melanoma cells. A similar experiment was performed using further homeopathic preparations sourced from kojic acid (KA), hydrogen peroxide (H2O2; HP), 6-biopterin (BP), and [Nle4, D-Phe7]-α-melanocyte-stimulating hormone (NLE), some of which are known to induce vitiligo or melano-destruction at physiological dose. Materials and Methods The homeopathic preparations of BP, KA, NLE, and HP were used in 30c potency. Alcohol and potentized alcohol were used as vehicle controls. Prior to starting the main experiment, the viability of B16F10 melanoma cells after treatment with study preparations was assayed. Melanin content (at 48 h and 96 h) and tyrosinase activity in melanocytes were determined. Results At the end of 48 hours, NLE and HP in 30c potency had a significantly greater melanin content (p = 0.015 and p = 0.039, respectively) compared with controls; BP and KA in 30c potency had no significant effects. No significant changes were seen at the end of 96 hours. KA, NLE, HP, and vehicle controls showed an inhibition of tyrosinase activity. Conclusion The study demonstrated melanogenic effects of two homeopathic preparations. Further research to evaluate the therapeutic efficacy of these medicines is warranted.


2019 ◽  
Vol 819 ◽  
pp. 118-123
Author(s):  
Wassana Riam-Amatakun ◽  
Panupan Limpachayaporn ◽  
Jhoan Rhea L. Pizon ◽  
Praneet Opanasopit ◽  
Nopparat Nuntharatanapon

Melanin is cutaneous pigment which level of its production determines skin complexion. Overproduction of melanin, frequently promoted by UV rays, results in darkening of the skin. Inhibition of tyrosinase activity, a core component in melanin biosynthesis, is one of the mechanisms of depigmenting agents. Hydroquinone and kojic acid are the examples of well-known whitening agents widely used in both pharmaceutical and cosmetic products. However, their adverse effect issues still needed to be overcome. A recent study showed that p-chlorophenyl benzyl ether (Cl-benz), a new synthetic compound, more strongly inhibited mushroom tyrosinase than kojic acid. In the current study, cytotoxicity, anti-melanogenic activity and anti-tyrosinase activity of Cl-benz were performed in mouse B16F10 melanoma cells compared to kojic acid. After 24 h of treatment on B16F10 cells, the cytotoxicity was not observed with Cl-benz and kojic acid. However, after incubation for 48 h, kojic acid at a concentration of 500 μM reduced cell viability less than 50%, whereas Cl-benz-treated cells showed negligible cytotoxicity. For cell-based assay, Cl-benz exhibited inhibitory effect similar to kojic acid. Melanin production in B16F10 cells was suppressed by Cl-benz in a dose dependent manner. One hundred micrograms of Cl-benz decreased melanin content in α-MSH by 66%. Moreover, the percentage of cellular tyrosinase activity of Cl-benz showed positive association with its corresponding melanin content. These results revealed that Cl-benz could inhibit melanogenesis via the mechanism of cellular tyrosinase inhibition. Accordingly, Cl-benz has potential to become a novel skin whitening agent in terms of efficacy and safety.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Hwayong Park ◽  
Kwang Hoon Song ◽  
Pil Mun Jung ◽  
Ji-Eun Kim ◽  
Hyunju Ro ◽  
...  

To identify the active compound arctigenin in Fructus Arctii (dried seed of medicinal plantArctium lappa) and to elucidate the inhibitory mechanism in melanogenesis, we analyzed melanin content and tyrosinase activity on B16BL6 murine melanoma and melan-A cell cultures. Water extracts of Fructus Arctii were shown to inhibit tyrosinase activity in vitro and melanin content inα-melanocyte stimulating hormone-stimulated cells to similar levels as the well-known kojic acid and arbutin, respectively. The active compound arctigenin of Fructus Arctii displayed little or no cytotoxicity at all concentrations examined and decreased the relative melanin content and tyrosinase activity in a dose-dependent manner. Melanogenic inhibitory activity was also identified in vivo with zebrafish embryo. To determine the mechanism of inhibition, the effects of arctigenin on tyrosinase gene expression and tyrosinase promoter activity were examined. Also in addition, in the signaling cascade, arctigenin dose dependently decreased the cAMP level and promoted the phosphorylation of extracellular signal-regulated kinase. This result suggests that arctigenin downregulates cAMP and the tyrosinase enzyme through its gene promoter and subsequently upregulates extracellular signal-regulated kinase activity by increasing phosphorylation in the melanogenesis signaling pathway, which leads to a lower melanin content.


Dose-Response ◽  
2021 ◽  
Vol 19 (4) ◽  
pp. 155932582110476
Author(s):  
Dayang Fredalina Basri ◽  
Leong Chen Lew ◽  
Raveena Vaidheswary Muralitharan ◽  
Tava Shelan Nagapan ◽  
Ahmad Rohi Ghazali

Pterostilbene is a potent antioxidant and anti-inflammatory agent. However, its chemopreventive effects via anti-tyrosinase activity and inhibitory effects on melanin content have not been reported previously. Hence, this study aimed to investigate the anti-melanogenic activity of pterostilbene on UVB-irradiated B164A5 mouse melanoma cells. The effects of pterostilbene and resveratrol on cell viability were determined by MTT assay, whereas melanin content and tyrosinase assay were employed to assess melanogenesis activity. Western blot analysis was performed to determine the tyrosinase expression. Based on the MTT assay, the IC50 value of pterostilbene on UVB-irradiated B164A5 cells was 34.0 ± 3.43 μM, in comparison to resveratrol (>100 μM). Next, 5 and 10 μM pterostilbene showed a significant dose-dependent inhibition ( P < .01) of tyrosinase activity in UVB-irradiated B164A5 cells at 37.14 ± 2.71% and 58.36 ± 6.8%, respectively. The findings from the tyrosinase assay also confirmed the downregulation of tyrosinase expression in UVB-irradiated B164A5 cells as measured by Western blot analysis. Finally, 10 μM pterostilbene showed a significantly decreased melanin content ( P < .01) in UVB-irradiated B164A5 cells, at 27.34 ± .98 μg/mL. In conclusion, pterostilbene showed anti-melanogenic activity that was 10 times more potent than resveratrol in the UVB-irradiated B164A5 cell.


BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6244-6261
Author(s):  
Si Young Ha ◽  
Ji Young Jung ◽  
Hee Young Kang ◽  
Tae-Heung Kim ◽  
Jae-Kyung Yang

Lespedeza bicolor (L. bicolor) is used for medicinal purposes because of its various biological and pharmacological activities. In this study, the effects of L. bicolor ethanol extract on the treatment of vitiligo were investigated. The determination of melanin content in melanocytes was measured using B16 melanoma cells and C57BL/6J Ler-vit/vit mice. Finally, the quercetin content in L. bicolor were qualitatively analyzed using HPLC. The results obviously indicated that the L. bicolor extract enhanced melanogenesis and increased tyrosinase activity in cultured melanoma cells and C57BL/6J Ler-vit/vit mice. Treatment with L. bicolor extract led to a higher content of melanin and eumelanin in C57BL/6J Ler-vit/vit mice hair than in control (untreated) mice, which demonstrated the therapeutic effect of hair-graying associated with vitiligo. There was a notable increase in melanocytes in the skin of C57BL/6J Ler-vit/vit mice treated with L. bicolor extract compared with the control. L. bicolor extract was a potent tyrosinase and melanin synthesis activator in B16 melanoma cells. C57BL/6J Ler-vit/vit mice treated with L. bicolor extract had significantly higher melanin content in hair than the untreated control. The results suggest that L. bicolor extract is a potential alternative treatment for improvement of vitiligo.


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