• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.193-200
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• 2019

Ceramide metabolism is known to be an essential etiology for various diseases, such as atopic dermatitis and Gaucher disease. Glucosylceramide synthase (GCS) is a key enzyme for the synthesis of glucosylceramide (GlcCer), which is a main ceramide metabolism pathway in mammalian cells. In this article, we developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to determine GCS activity using synthetic non-natural sphingolipid C8-ceramide as a substrate. The reaction products, C8-GlcCer for GCS, could be separated on a C18 column by reverse-phase high-performance liquid chromatography (HPLC). Quantification was conducted using the multiple reaction monitoring (MRM) mode to monitor the precursor-to-product ion transitions of m/z $588.6{\rightarrow}264.4$ for C8-GlcCer at positive ionization mode. The calibration curve was established over the range of 0.625-160 ng/mL, and the correlation coefficient was larger than 0.999. This method was successfully applied to detect GCS in the human hepatocellular carcinoma cell line (HepG2 cells) and mouse peripheral blood mononuclear cells. We also evaluated the inhibition degree of a known GCS inhibitor 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) on GCS enzymatic activity and proved that this method could be successfully applied to GCS inhibitor screening of preventive and therapeutic drugs for ceramide metabolism diseases, such as atopic dermatitis and Gaucher disease.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.105.2-105.2
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• 2003

Recently, several reports suggest that ceramide formation has been implicated in the apoptosis signaling in response to chemotherapeutic agents. In this study, to enhance paclitaxel-mediated cytotoxicity and endogenous ceramide levels, we blocked ceramide metabolism using an inhibitor of glucosylceramide synthase, l-phenyl-2- dacanoylamino-3-morpholino-l-propanol(PDMP) and SM synthase, D609. Exposure of human breast cancer cells to paclitaxel accumulated de novo ceramide synthesis by enhancement of SPT activity 1.2-fold, whereas ceramide synthase activity was not altered. (omitted)

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.2
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• pp.105-117
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• 2020

Agaricus blazei Murill (Almond mushroom) has many beneficial effects, such as anti-cancer, immuneenhancement, and anti-obesity. Also, its skin benefits have been reported for antioxidant, anti-inflammatory, and whitening. In order to elucidate these effects, many studies have been conducted. In this study, we reconfirmed the skin efficacy of the extract of the mushrooms mushrooms. The Agaricus blazei extract showed inhibition of melanin synthesis, enhancement of collagen synthesis, and up-regulation of gene expression (hyaluronan syntahase-2, 3 and aquaporin-3) at 100 ㎍/mL. and identified the ingredients from the extract. We further investigated them to find an applicability as cosmetic ingredients. The ingredients were confirmed comparison of their spectroscopic data with literature values. They were identified as being ergosterol (1), 5-dihydroergosterol (2), cerevisterol (3), cerebroside B (4), cerebroside D (5), adenosine (6), and benzoic acid (7). Among these compounds, we evaluated skin efficacy for two cerebrosides and three ergosterol derivatives that have not been reported its efficacy. As a result, 5-dihydroergosterol (2) inhibited melanogenesis in B16F10 and promoted collagen biosynthesis in human dermal fibroblast. In addition, cerevisterol (3), cerebroside B (4), and cerebroside D (5) inhibited NO production in RAW 264.7 cell. In particular, cerebroside D (5) increased the expression of hyaluronan synthase-2 and aquaporin-3 genes in HaCaT. These results suggest that Agaricus blazei extract and isolated compounds can be used as cosmetic ingredients.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.5
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• pp.251-258
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• 2011

Here we have investigated how lactosylceramide (LacCer) modulates gene expression of adhesion molecules in TNF-${\alpha}$ and IFN ${\gamma}$ (CM)-stimulated astrocytes. We have observed that stimulation of astrocytes with CM increased the gene expression of ICAM-1 and VCAM-1. D-Threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) and N-butyldeoxynojirimycin (NBDNJ), inhibitors of glucosylceramide synthase (GLS) and LacCer synthase (galactosyltransferase, GalT-2), inhibited the gene expression of ICAM-1 and VCAM-1 and activation of their gene promoter induced by CM, which were reversed by exogenously supplied LacCer. Silencing of GalT-2 gene using its antisense oligonucleotides also attenuated CM-induced ICAM-1 and VCAM-1 expression, which were reversed by LacCer. PDMP treatment and silencing of GalT-2 gene significantly reduced CM-induced luciferase activities in NF-${\kappa}B$, AP-1, GAS, and STAT-3 luciferase vectors-transfected cells. In addition, LacCer reversed the inhibition of NF-${\kappa}B$ and STAT-1 luciferase activities by PDMP. Taken together, our results suggest that LacCer may play a crucial role in the expression of ICAM-1 and VCAM-1 via modulating transcription factors, such as NF-${\kappa}B$, AP-1, STAT-1, and STAT-3 in CM-stimulated astrocytes.