Inhibition of Melanogenesis by Some Well-Known Polyphenolics: A Review

Abstract

: Melanogenesis is simply defined as production of melanin in melanosomes by melanocytes through a complex process. Melanin, a pigment derived from L-tyrosine, comes into two forms, namely eumelanin (brownish to black) and pheomelanin (red to yellow). Melanin synthesis starts via the hydroxylation of L-tyrosine to L-3,4-dihydroxyphenylalanine (DOPA) catalyzed by the enzyme known as tyrosinase (TYR), which triggers further conversion reaction to DOPAquinone and then to DOPAchrome. Additionally, this process is also related to two more proteins, i.e. oxygenase TYR-related protein 1 (TYRP1), and dopachrome tautomerase TYRP2 (or DCT). However, TYR located in the melanosomal membrane still stands as the key enzyme to initiate the whole process of melanogenesis. Due to some deficits, melanogenesis may emerge as hypo- or hyperpigmentation in the skin. High production of melanin in melanocytes leads to hyperpigmentationrelated skin disorders including freckles, melasma, melanoma, etc., that may cause displeasure in personal appearance and reduction of quality of life. Consequently, several melanogenesis inhibitors of synthetic and natural origins have been developed up to date, though most of them have been reported with serious side effects. For this reason, an extensive research is still going on to find novel and more effective melanogenesis inhibitors with less side effects. In this sense, particularly flavonoids, catechins, and stilbenes from plants have been a hope to discover new inhibitors which attract a great attention from scientists. In this review, promising natural products effective in melanogenesis inhibition will be scrutinized.

Theoretical Studies of Cyanophycin Dipeptides as Inhibitors of Tyrosinases

“…Both sequences possess the tyrosinase and hemocyanin CuB-binding region signature D-P-x-F-[LIVMFYTW]-x(2)-H-x(3)-D and the CuA-binding region signature H-x(4,5)-F-[LIVMFTP]-x-[FW]-H-R-x(2)-[LVMT]-x(3)-E ( Figure 2 and Figure 3 ). According to a previous study, seven histidine residues (His180, His202, His211, His363, His367, His389, His390) participate in copper chelation and substrate binding [ 10 , 53 ]. Human tyrosinase possesses the EGF domain ( Figure 2 and Figure 3 ), which is absent in the mushroom tyrosinase.…”

Complete Genome Sequence and Cosmetic Potential of Viridibacillus sp. JNUCC6 Isolated from Baengnokdam, the Summit Crater of Mt. Halla

“…Accordingly, it has been suggested that melanin production is primarily controlled by the expression and activation of tyrosinase. Therefore, the main strategy is to target tyrosinase, with increasing interest in the use of natural products as tyrosinase inhibitors [11,12]. The established murine B16 melanoma cell (B16F10 cells) line offers a model system with readily quantifiable markers characteristic of differentiation, including melanogenesis [21].…”

“…Moreover, green and environmentally friendly organic products have become popular. Ultimately, research and discovery of safe and healthy skin-whitening ingredients have become a trend in modern development [11,12]. Hyperpigmentation is one of the most common skin diseases that affects both men and women of all ethnic groups owing to a number of factors, such as ultraviolet (UV) exposure and skin inflammation.…”

“…Hyperpigmentation is associated with reduced melanin production, a major pigment that controls skin and hair color. Excessive production of melanin can cause severe skin cancer by accumulating melanin on the skin and forming freckles; therefore, it is necessary to suppress melanin production to prevent excessive skin pigmentation [9][10][11][12]. In addition, a good anti-inflammatory effect may exhibit a synergistic whitening effect by reducing the damage caused by oxidation and inflammation of the skin [13][14][15].…”

Synthesis and biochemical evaluation of 5-(pyridin-4-yl)-3-(alkylsulfanyl)-4H-1,2,4-triazol-4-amine-based inhibitors of tyrosinase from Agaricus bisporus

“…2 Based on the knowledge of this enzymatic pathway, the targeting of tyrosinase inhibitors (TYRIs) has demonstrated efficacy in cosmetic and dermatology applications. 4 To address this issue, a large number of inhibitors from natural and synthetic sources have been reported in the literature; 1,[5][6][7] they have generally been identified on the basis of their ability to inhibit tyrosinase from Agaricus bisporus (AbTYR), which represents a readily and cheap protocol to preliminarily screen TYRIs. 8,9 In turn, the best active AbTYR inhibitors were further studied using advanced biological methods, as well as human tyrosinase (hTYR) screening validation through cell-free crude extracts of tyrosinase-expressing cell lines and recombinant hTYR.…”