Melanosomes, isolated by centrifugal separation from culture broth of B16 melanoma cells derived from mouse, were observed by scanning electron microscopy (SEM), and by transmission electron microscopy (TEM). Some int...Melanosomes, isolated by centrifugal separation from culture broth of B16 melanoma cells derived from mouse, were observed by scanning electron microscopy (SEM), and by transmission electron microscopy (TEM). Some interesting structural features were found inside and outside of the melanosomes. By SEM observation, the melanosomes were ellipsoid shape, their surface was not smooth and was covered with rough substructure, 10 to 20 nm particles. By TEM, uneven structure and micro particles were observed in the melanosomes. Furthermore, three-dimensional analysis was tried by using the ultra-high voltage electron microscopy(UHVEM). Micrographs of the melanosomes were taken at various tilted angles by UHVEM, after preparing 500 nm thickness specimens stained with lead citrate. From the micrographs collected, the three-dimensional structures were reconstructed by using i-mode software. Melanin stained by lead and non stained parts was clearly observed in the reconstructed structure. Non stained parts were round, regular size, and distributed widely in the melanosomes.展开更多
Objective:To explore the anti-melanogenic potential of Cyrtomium falcatum.Methods:The effects of Cyrtomium falcatum crude extract and its solvent fractions on tyrosinase activity,melanin content,and the expressions of...Objective:To explore the anti-melanogenic potential of Cyrtomium falcatum.Methods:The effects of Cyrtomium falcatum crude extract and its solvent fractions on tyrosinase activity,melanin content,and the expressions of melanogenesis-related genes and proteins were analyzed inα-melanocyte-stimulating hormone(α-MSH)-stimulated B16F10 cells.Results:α-MSH treatment significantly increased tyrosinase activity,and extracellular and intracellular melanin content,as well as the expression levels of tyrosinase,microphthalmia-associated transcription factor(MITF),tyrosinase-related protein(TRP)-1,and TRP-2 in B16F10 cells.Treatment with Cyrtomium falcatum crude extract and its solvent fractions reduced tyrosinase activity and extracellular and intracellular melanin content and downregulated the expression levels of tyrosinase,MITF,TRP-1,and TRP-2 in a dose-dependent manner.Conclusions:Cyrtomium falcatum has potential anti-melanogenesis effects and can be used as a potential source material in cosmeceutical industry for the research and development of novel lead molecules with whitening properties.展开更多
A new derivative of triterpene named Erigeronol 1 was isolated from the EtOH extract of the aerial part of Conyza canadensis together with 15 known compounds for the first time from this plant.The structure of Erigero...A new derivative of triterpene named Erigeronol 1 was isolated from the EtOH extract of the aerial part of Conyza canadensis together with 15 known compounds for the first time from this plant.The structure of Erigeronol 1 was elucidated as 3-O-（hydroxyacetyl） -23,28-dihydroxy-β-amyrin by hydrolysis and spectroscopic analysis.Erigeronol 1 showed potent cytotoxic activity with IC_（50） value of 7.77±0.47μg/mL against melanoma B16 determined by the 3-（4,5-dimethylthiazo-2-yl）-2,5-diphenyltetrazolium bromide（MTT） method.展开更多
A battery of sex steroids were used to check their effect on mouse melanoma (B16F10) cell growth in-vitro. Progesterone and its synthetic receptor antagonist RU-486 showed maximum inhibition on in-vitro melanoma cell ...A battery of sex steroids were used to check their effect on mouse melanoma (B16F10) cell growth in-vitro. Progesterone and its synthetic receptor antagonist RU-486 showed maximum inhibition on in-vitro melanoma cell growth [1]. Further research work showed that the inhibition by progesterone was not a toxic, spurious or non-specific effect on mouse melanoma cell growth and the inhibition by progesterone was not mediated through progesterone receptor.展开更多
文摘Melanosomes, isolated by centrifugal separation from culture broth of B16 melanoma cells derived from mouse, were observed by scanning electron microscopy (SEM), and by transmission electron microscopy (TEM). Some interesting structural features were found inside and outside of the melanosomes. By SEM observation, the melanosomes were ellipsoid shape, their surface was not smooth and was covered with rough substructure, 10 to 20 nm particles. By TEM, uneven structure and micro particles were observed in the melanosomes. Furthermore, three-dimensional analysis was tried by using the ultra-high voltage electron microscopy(UHVEM). Micrographs of the melanosomes were taken at various tilted angles by UHVEM, after preparing 500 nm thickness specimens stained with lead citrate. From the micrographs collected, the three-dimensional structures were reconstructed by using i-mode software. Melanin stained by lead and non stained parts was clearly observed in the reconstructed structure. Non stained parts were round, regular size, and distributed widely in the melanosomes.
基金This work was supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2023R1A2C1006268 and RS-2023-00212560).
文摘Objective:To explore the anti-melanogenic potential of Cyrtomium falcatum.Methods:The effects of Cyrtomium falcatum crude extract and its solvent fractions on tyrosinase activity,melanin content,and the expressions of melanogenesis-related genes and proteins were analyzed inα-melanocyte-stimulating hormone(α-MSH)-stimulated B16F10 cells.Results:α-MSH treatment significantly increased tyrosinase activity,and extracellular and intracellular melanin content,as well as the expression levels of tyrosinase,microphthalmia-associated transcription factor(MITF),tyrosinase-related protein(TRP)-1,and TRP-2 in B16F10 cells.Treatment with Cyrtomium falcatum crude extract and its solvent fractions reduced tyrosinase activity and extracellular and intracellular melanin content and downregulated the expression levels of tyrosinase,MITF,TRP-1,and TRP-2 in a dose-dependent manner.Conclusions:Cyrtomium falcatum has potential anti-melanogenesis effects and can be used as a potential source material in cosmeceutical industry for the research and development of novel lead molecules with whitening properties.
文摘A new derivative of triterpene named Erigeronol 1 was isolated from the EtOH extract of the aerial part of Conyza canadensis together with 15 known compounds for the first time from this plant.The structure of Erigeronol 1 was elucidated as 3-O-（hydroxyacetyl） -23,28-dihydroxy-β-amyrin by hydrolysis and spectroscopic analysis.Erigeronol 1 showed potent cytotoxic activity with IC_（50） value of 7.77±0.47μg/mL against melanoma B16 determined by the 3-（4,5-dimethylthiazo-2-yl）-2,5-diphenyltetrazolium bromide（MTT） method.
文摘A battery of sex steroids were used to check their effect on mouse melanoma (B16F10) cell growth in-vitro. Progesterone and its synthetic receptor antagonist RU-486 showed maximum inhibition on in-vitro melanoma cell growth [1]. Further research work showed that the inhibition by progesterone was not a toxic, spurious or non-specific effect on mouse melanoma cell growth and the inhibition by progesterone was not mediated through progesterone receptor.
