Mangosteen leaf extract increases melanogenesis in B16F1 melanoma cells by stimulating tyrosinase activity in vitro and by up-regulating tyrosinase gene expression

Abstract

Abstract. Melanin synthesis is stimulated by various effectors, including α-melanocyte stimulating hormone (α-MSH), cyclic AMP (cAMP)-elevating agents (forskolin, isobutylmethylxantine, glycyrrhizin) and ultraviolet light. Our investigation focused on the identification of the melanogenic efficacy of mangosteen (Garcinia mangostana) leaf extract with regard to its effects on melanogenesis in B16F1 melanoma cells, since it has been known to possess strong anti-oxidant activities. The mangosteen leaf extract was found to stimulate melanin synthesis and tyrosinase activity in a dose-dependent manner without any significant effects on cell proliferation. Cytotoxicity of the extract was measured using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; the highest concentration of the extract that did not affect cell viability was 32 µg/ml. Formation of melanin from cultured B16F1 melanoma induced by extract treatment was estimated using spectrophotometry. In order to clarify the subsequent mechanism of tyrosinase activation by the extract, the levels of tyrosinase expression in B16F1 melanoma were examined using an intracellular tyrosinase assay and tyrosinase zymography. Up-regulation of intracellular tyrosinase expression seemed to correlate with an increase in microphtalmia-associated transcription factor (MITF) protein levels since MITF is the key factor for genes involved in melanogenesis. Both of the results showed that tyrosinase activity was markedly enhanced from extract-treated cells. The overall results suggest that mangosteen leaf extract may be a promising candidate for the treatment of hypopigmentation disorder and useful for selftanning cosmetic products.

Pigmentation Effect of Rice Bran Extracted Minerals Comprising Soluble Silicic Acids

“…The melanin contents in melanocytes were determined using a previously published method [13] with modifications. After removing the culture media from the plates, the cells were lysed with 10% DMSO solution, dissolved in 1 M NaOH, and boiled at 80°C for 2 h. Then, the cells were centrifuged at 15000 rpm for 15 min.…”

“…Intracellular tyrosinase activity was measured using a previously described method [13] with slight modifications. Melanoblasts were seeded at 1 × 10 4  cells/well in 6-well plates and cultured for 3 days in differentiation media.…”

Antioxidant and tyrosinase inhibition activity of the fertile fronds and rhizomes of three different Drynaria species

“…Interestingly however, most of the extracts exhibited tyrosinase enhancement activity, effectively acting as tanning agents. While reports on tyrosinase inhibition are more common, a number of extracts are known to increase melanogenesis, including kava rhizomes, lotus flowers and mangosteen leaves [ 33 ]. Although phenolic compounds are often tyrosinase inhibitors, several are capable of acting as tyrosinase activity enhancers, such as naringenin [ 5 ] and 4′-O-β- d -glucopyranosyl-(1→2)-β- d -glucopyranosyl-quercetin-3-O-β- d -glucopyranosyl-(1→4)-β- d -glucopyranoside [ 34 ].…”

“…Macrocycles such as cryptand and crown ethers are also capable of enhancing tyrosinase activity by acting as carriers for water molecules, which in turn increases the enzyme’s activity [ 35 ]. Tyrosinase enhancement can see application in skin care products designed to reduce UV damage for skin cancer prevention [ 34 ], and as a treatment for hypopigmentation [ 33 ]. It can also prove useful in the cosmetics industry, for self-tanning [ 33 ].…”

“…Tyrosinase enhancement can see application in skin care products designed to reduce UV damage for skin cancer prevention [ 34 ], and as a treatment for hypopigmentation [ 33 ]. It can also prove useful in the cosmetics industry, for self-tanning [ 33 ]. The exact causal agent for this tyrosinase enhancement would require further investigation, particularly in the fronds of D. sparsisora , which showed remarkable tyrosinase enhancement activity.…”