Effect of polysaccharide FMP-1 from Morchella esculenta on melanogenesis in B16F10 cells and zebrafish
FOOD & FUNCTION
Authors: Cai, Zheng-Nan; Li, Wan; Mehmood, Shomaila; Pan, Wen-Juan; Wu, Qing-Xi; Chen, Yan; Lu, Yong-Ming
Abstract
Polysaccharides from Morchella esculenta are known to exhibit diverse bioactivities, while an anti-melanogenesis effect has been barely addressed. Herein, the anti-melanogenesis activity of a heteropolysaccharide from M. esculenta (FMP-1) was investigated in vitro and in vivo. FMP-1 had no significant cytotoxic effect on B16F10 melanoma cells as well as zebrafish larvae, but did reduce melanin contents and tyrosinase activities in both of them. Treatment with FMP-1 also effectively suppressed the expression of melanogenesis-related proteins, including MC1R, MITF, TRP-1 and TRP-2, through decreasing the phosphorylation of cyclic adenosine monophosphate response element-binding protein (CREB). Moreover, the mitogen-activated protein kinase (MAPK) pathway was observed mediating FMP-1's inhibitory effect against melanin production. Specifically, FMP-1 treatment markedly inhibited the activation of phosphorylation of p38 mitogen-activated protein kinase. These results suggested that FMP-1's inhibitory effect against melanogenesis is mediated by the inhibition of CREB and p38 signaling pathways, thereby resulting in the downstream repression of melanogenesis-related proteins and the subsequent melanin production. These data provide insight into FMP-1's potential anti-melanogenesis effect in food and cosmetic industries.
Does the gene matter? Genotype-phenotype and genotype-outcome associations in congenital melanocytic naevi
BRITISH JOURNAL OF DERMATOLOGY
Authors: Polubothu, S.; McGuire, N.; Al-Olabi, L.; Baird, W.; Bulstrode, N.; Chalker, J.; Josifova, D.; Lomas, D.; O'Hara, J.; Ong, J.; Rampling, D.; Stadnik, P.; Thomas, A.; Wedgeworth, E.; Sebire, N. J.; Kinsler, V. A.
Abstract
Background Genotype-phenotype studies can identify subgroups of patients with specific clinical features or differing outcomes, which can help shape management. Objectives To characterize the frequency of different causative genotypes in congenital melanocytic naevi (CMN), and to investigate genotype-phenotype and genotype-outcome associations. Methods We conducted a large cohort study in which we undertook MC1R genotyping from blood, and high-sensitivity genotyping of NRAS and BRAF hotspots in 156 naevus biopsies from 134 patients with CMN [male 40%; multiple CMN 76%; projected adult size (PAS) > 20 cm, 59%]. Results Mosaic NRAS mutations were detected in 68%, mutually exclusive with BRAF mutations in 7%, with double wild-type in 25%. Two separate naevi were sequenced in five of seven patients with BRAF mutations, confirming clonality. Five of seven patients with BRAF mutations had a dramatic multinodular phenotype, with characteristic histology distinct from classical proliferative nodules. NRAS mutation was the commonest in all sizes of CMN, but was particularly common in naevi with PAS > 60 cm, implying more tolerance to that mutation early in embryogenesis. Facial features were less common in double wild-type patients. Importantly, the incidence of congenital neurological disease, and apparently of melanoma, was not altered by genotype; no cases of melanoma were seen in BRAF-mutant multiple CMN, however, this genotype is rare. Conclusions CMN of all sizes are most commonly caused by mutations in NRAS. BRAF is confirmed as a much rarer cause of multiple CMN, and appears to be commonly associated with a multinodular phenotype. Genotype in this cohort was not associated with differences in incidence of neurological disease in childhood. However, genotyping should be undertaken in suspected melanoma, for guidance of treatment.