Sageretia thea fruit extracts rich in methyl linoleate and methyl linolenate downregulate melanogenesis via the Akt/GSK3β signaling pathway

BACKGROUND/OBJECTIVES: Sageretia thea is traditionally used as a medicinal herb to treat various diseases, including skin disorders, in China and Korea. This study evaluated the inhibitory effect of Sageretia thea fruit on melanogenesis and its underlying mechanisms in B16F10 mouse melanoma cells. The active chemical compounds in anti-melanogenesis were determined in Sageretia thea. MATERIALS/METHODS: Solvent fractions from the crude extract were investigated for anti-melanogenic activities. These activities and the mechanism of anti-melanogenesis in B16F10 cells were examined by determining melanin content and tyrosinase activity, and by performing western blotting. RESULTS: The n-hexane fraction of Sageretia thea fruit (HFSF) exhibited significant anti-melanogenic activity among the various solvent fractions without reducing viability of B16F10 cells. The HFSF suppressed the expression of tyrosinase and tyrosinase-related protein 1 (TRP1). The reduction of microphthalmia-associated transcription factor (MITF) expression by the HFSF was mediated by the Akt/glycogen synthase kinase 3 beta (GSK3β) signaling pathway, which promotes the reduction of β-catenin. Treatment with the GSK3β inhibitor 6-bromoindirubin-3'-oxime (BIO) restored HFSF-induced inhibition of MITF expression. The HFSF bioactive constituents responsible for anti-melanogenic activity were identified by bioassay-guided fractionation and gas chromatography-mass spectrometry analysis as methyl linoleate and methyl linolenate. CONCLUSIONS: These results indicate that HFSF and its constituents, methyl linoleate and methyl linolenate, could be used as whitening agents in cosmetics and have potential for treating hyperpigmentation disorders in the clinic.

Effects of Lobetyolin, Lobetyol and Methyl linoleate on Secretion, Production and Gene Expression of MUC5AC Mucin from Airway Epithelial Cells / 결핵및호흡기질환

BACKGROUND: In this study, we investigated whether lobetyolin, lobetyol, and methyl linoleate derived from Codonopsis pilosula affect MUC5AC mucin secretion, production, and gene expression from airway epithelial cells. METHODS: Confluent NCI-H292 cells were pretreated with lobetyolin, lobetyol, or methyl linoleate for 30 minutes and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 hours. The MUC5AC mucin gene expression, and mucin protein production and secretion were measured by reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: Lobetyolin, lobetyol, and methyl linoleate inhibited the gene expression of MUC5AC mucin induced by PMA; lobetyolin did not affect PMA-induced MUC5AC mucin production. However, lobetyol and methyl linoleate inhibited the production of MUC5AC mucin; lobetyolin and lobetyol did not significantly affect PMA-induced MUC5AC mucin secretion from NCI-H292 cells. However, methyl linoleate decreased the MUC5AC mucin secretion. CONCLUSION: These results suggest that among the three compounds, methyl linoleate can regulate gene expression, production, and secretion of MUC5AC mucin by directly acting on the airway epithelial cells.

Composição do óleo essencial de Sinningia aggregata / Composition of essential oil of Sinningia aggregata

O óleo essencial de Sinningia aggregata (Ker. Gawl.) Wiehler (Gesneriaceae) foi extraído por hidrodestilação e analisado por CG e CG/EM. Foram identificados 17 compostos, representando 91,8 por cento do óleo. O óleo é constituído principalmente por compostos alifáticos de cadeia longa (49,8 por cento) e sesquiterpenos oxigenados (40,2 por cento). Os principais componentes foram: linoleato de metila (28,4 por cento), 1-octadecanol (16,9 por cento), acetato de (Z)-nerolidila (8,8 por cento), espatulenol (7,8 por cento) e (E)-nerolidol (6,7 por cento). Monoterpenos e fenilpropanóides não foram encontrados. Este é o primeiro relato de estudo de óleo essencial na família Gesneriaceae.

The essential oil isolated by hydrodistillation from the aerial parts of Sinningia aggregata (Ker. Gawl.) Wiehler (Gesneriaceae) was analyzed by capillary GC and GC/MS. Seventeen components were identified, representing 91,8 percent of the total oil. The oil was characterized by a high content of long-chain aliphatic compounds (49,8 percent) and oxygenated sesquiterpenes (40,2 percent). The two major components were methyl linoleate (28,4 percent) and 1-octadecanol (16,9 percent). Among the sesquiterpenes, (Z)-nerolidol acetate (8,8 percent), spathulenol (7,8 percent) and (E)-nerolidol (6,7 percent) are present in appreciable amounts. Monoterpenes and phenylpropanoids were not found in the oil.