Fucoidan displays diverse biological functions, including antiviral, antitumor, and antioxidant qualities, according to studies. This blog post is dedicated to introducing the study “EFFECT OF FUCOIDAN ON B16 MURINE MELANOMA CELL MELANIN FORMATION AND APOPTOSIS,” authored by Zhi-Jiang Wang et al. The study investigated how fucoidan, extracted from Fucus vesiculosus, influences melanin production in melanoma cells, considering fucoidan’s known ability to inhibit tyrosinase and fight cancer. In addition to exploring the effects of fucoidan on B16 melanoma cells, this research also delves into fucoidan’s potential to impede tyrosinase activity within melanin-producing B16 melanoma cells and the resulting influence on melanin synthesis.
In the study, the inhibitory concentration of fucoidan resulting in a 50% reduction in activity (IC50) was estimated to be 550 ± 4.3 µg/mL. The research indicated that fucoidan’s capacity to hinder tyrosinase activity is altered when tyrosinase exists independently within cells. These results demonstrated that the ability of fucoidan to inhibit cellular tyrosinase is far superior to its ability to inhibit free tyrosinase (see Figure. 1).
The research explored the role of fucoidan in regulating melanin production within B16 melanoma cells. Figure 2 shows that fucoidan dose-dependently reduced intracellular melanin content. Figures 1 and 2 suggest that reduced melanin synthesis is due to a decrease in the activity of tyrosinase, a key enzyme in melanin synthesis.
Tyrosinase, TRP-1, and TRP-2 stimulate the production of melanin, and the expression of these components is regulated by MITF, a critical transcription factor. These proteins were evaluated using Western blotting after 48 hours of treatment with different concentrations of fucoidan. Results showed that the expression of TRP-1, TRP-2, and MITF was not significantly affected, but the expression of tyrosinase and MITF increased.
Cell viability was examined to elucidate the impact of fucoidan on the creation of melanin within cells. The effect of different concentrations of fucoidan (0–600 µg/mL) on B16 melanoma cell proliferation was assessed using a CCK-8 assay to measure cell viability. The addition of fucoidan dose-dependently affected B16 melanoma cell proliferation. Fucoidan dose-dependently reduced the number of viable cells, and after the addition of 600 µg/mL of fucoidan, cell viability decreased to 46.37 ± 2.6%. The IC50 was 530 ± 3.32 µg/mL. Fucoidan not only inhibited tyrosinase activity but also showed excellent inhibitory effects on melanocytes. The data indicate that fucoidan effectively lightens skin at both the molecular and cellular levels.
The B16 melanoma cells were treated with fucoidan (550µg/mL) for 48 hours, and then observed using a phase-contrast microscope. In the control group, B16 melanoma cells proliferated well, with dense, regular cell growth. Unlike the control group, the fucoidan-treated group’s cells showed a significant decrease in activity within 48 hours, changes in their form, and lost their contact trophism. Fucoidan demonstrated significant anti-melanocyte activity (see Figure 3).
The inhibitory effect of fucoidan on B16 cell proliferation was examined by measuring apoptosis in cells treated with varying concentrations of fucoidan using Annexin V-FITC/PI staining and flow cytometry. The results showed that the apoptosis rate increased from 3.01±1.02% to 13.74±2.47% in cells treated with 550µg/mL of fucoidan for 48 hours. This suggests that fucoidan significantly induced cell apoptosis.
In conclusion, based on earlier and current research, the key finding is that fucoidan prevented B16 melanoma cells from multiplying. Fucoidan enhanced tyrosinase expression. Furthermore, fucoidan inhibited tyrosinase activity in B16 mouse melanoma cells. In addition, B16 mouse cell tyrosinase demonstrated a stronger inhibitory effect than the previously observed inhibition by free cell-derived mushroom tyrosinase. Fucoidan prompted melanocyte apoptosis while also successfully preventing extracellular tyrosinase. Fucoidan could potentially be a promising ingredient that is useful for the purpose of making skin lighter.
Source: Afr J Tradit Complement Altern Med. 2017 Jun 5;14(4):149–155. doi: 10.21010/ajtcam.v14i4.18