Sphinganine 1-phosphate metabolism in cultured skin fibroblasts: evidence for the existence of a sphingosine phosphatase

On addition of [4,5-3H]sphinganine 1-phosphate to human fibroblast monolayers, the label was efficiently removed from the culture medium. In contrast with the reported stability of phosphorylated sphingenine in 3T3 cells [Desai, Zhang, Olivera, Mattie and Spiegel (1992). J. Biol. Chem. 267, 23122-23128] and B16 melanoma cells [Sadahira, Ruan, Hakomuri and Igarashi (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 9686-9690], sphinganine 1-phosphate appeared to be subjected to a fast and extensive metabolism in fibroblasts, the major pathways being cleavage and dephosphorylation. The first of these pathways, catalysed by sphingosine-phosphate lyase, resulted in the formation of labelled palmitaldehyde, which was recovered, mainly after oxidation, in glycerophospholipids in an ester bond. A smaller part of the palmitaldehyde was reduced and incorporated in alk(en)ylphospholipids. Dephosphorylation of spinganine 1-phosphate, a hitherto overlooked pathway catalysed by an unknown phosphatase(s), gave rise to sphinganine, which was converted by N-acylation into ceramide and then incorporated in spingomyelin and glycosphingolipids.

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Glycoprotein metabolism in normal and β-mannosidase-deficient cultured goat skin fibroblasts

Biochemical Journal ◽

10.1042/bj2340175 ◽

1986 ◽

Vol 234 (1) ◽

pp. 175-183 ◽

Cited By ~ 19

Author(s):

L W Hancock ◽

M Z Jones ◽

G Dawson

Keyword(s):

Culture Medium ◽

Human Fibroblasts ◽

Skin Fibroblasts ◽

Medium Ph ◽

Cytosolic Ph ◽

Catabolic Pathways ◽

No Conversion ◽

Lysosomal Ph ◽

Cultured Skin ◽

Oligosaccharide Structures

Cultured skin fibroblasts established from goats affected with beta-mannosidosis, an inherited neurovisceral storage disorder, showed an absence of lysosomal beta-mannosidase activity and the corresponding accumulation of a trisaccharide (TS) with the structure Man beta (1→4)GlcNAc beta (1→4)GlcNAc (0.4 mumol/g) and lesser amounts (0.15 mumol/g) of a Man beta (1→4)GlcNAc disaccharide (DS). By using purified storage TS isolated from fibroblasts metabolically labelled with [3H]GlcN, no conversion of TS into DS could be demonstrated in homogenates of affected cells at either lysosomal pH (4.4) or cytosolic pH (6.1), or in the culture medium (pH 7.0) of affected cells. Both TS and DS were secreted into the culture medium by affected fibroblasts. When affected fibroblasts were treated with tunicamycin before labelling with [3H]GlcN, the accumulation of both labelled TS and DS was completely inhibited. Treatment of both affected and normal goat fibroblasts with swainsonine resulted in the inhibition of lysosomal alpha-mannosidase activity and in the accumulation of the same labelled oligosaccharides in both. The major storage pentasaccharide from both normal and affected swainsonine-treated fibroblasts was sensitive to digestion with alpha-mannosidase and endo-beta-N-acetylhexosaminidase D, suggesting a branched mannose structure and a chitobiose core. In the absence of evidence for the existence of unusual N-linked glycoprotein-associated chitotriose oligosaccharide structures in affected goat fibroblasts, it must be concluded that degradative pathways for N-linked oligosaccharides are similar in both normal and affected goat fibroblasts, and that these pathways differ from catabolic pathways in human fibroblasts.

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Electron Microscopy of Fibroblasts from Myotonic Muscular Dystrophy Patients

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098976 ◽

1981 ◽

Vol 39 ◽

pp. 498-499

Author(s):

S. E. Miller ◽

G. B. Hartwig ◽

R. A. Nielsen ◽

A. P. Frost ◽

A. D. Roses

Keyword(s):

Electron Microscopy ◽

Muscular Dystrophy ◽

Genetic Diseases ◽

Skin Fibroblasts ◽

Inborn Errors ◽

Cytoplasmic Inclusions ◽

Cultured Skin ◽

Myotonic Muscular Dystrophy ◽

Glycosaminoglycan Metabolism

Many genetic diseases can be demonstrated in skin cells cultured in vitro from patients with inborn errors of metabolism. Since myotonic muscular dystrophy (MMD) affects many organs other than muscle, it seems likely that this defect also might be expressed in fibroblasts. Detection of an alteration in cultured skin fibroblasts from patients would provide a valuable tool in the study of the disease as it would present a readily accessible and controllable system for examination. Furthermore, fibroblast expression would allow diagnosis of fetal and presumptomatic cases. An unusual staining pattern of MMD cultured skin fibroblasts as seen by light microscopy, namely, an increase in alcianophilia and metachromasia, has been reported; both these techniques suggest an altered glycosaminoglycan metabolism An altered growth pattern has also been described. One reference on cultured skin fibroblasts from a different dystrophy (Duchenne Muscular Dystrophy) reports increased cytoplasmic inclusions seen by electron microscopy. Also, ultrastructural alterations have been reported in muscle and thalamus biopsies from MMD patients, but no electron microscopical data is available on MMD cultured skin fibroblasts.

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Possible Werner syndrome. A unique association with spontaneous digital gangrene in infancy and decreased life span of cultured skin fibroblasts

Archives of Dermatology ◽

10.1001/archderm.128.9.1238 ◽

1992 ◽

Vol 128 (9) ◽

pp. 1238-1242 ◽

Cited By ~ 1

Author(s):

S. Iijima

Keyword(s):

Life Span ◽

Werner Syndrome ◽

Skin Fibroblasts ◽

Cultured Skin ◽

Unique Association

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Elucidation of Melanogenesis-Associated Signaling Pathways Regulated by Argan Press Cake in B16 Melanoma Cells

Nutrients ◽

10.3390/nu13082697 ◽

2021 ◽

Vol 13 (8) ◽

pp. 2697

Author(s):

Thouria Bourhim ◽

Myra O. Villareal ◽

Chemseddoha Gadhi ◽

Hiroko Isoda

Keyword(s):

Signaling Pathways ◽

Press Cake ◽

Global Gene Expression ◽

Melanoma Cells ◽

B16 Melanoma ◽

Dependent Manner ◽

Melanin Biosynthesis ◽

B16 Melanoma Cells ◽

Pigmentary Disorders ◽

Argan Oil

The beneficial effect on health of argan oil is recognized worldwide. We have previously reported that the cake that remains after argan oil extraction (argan press-cake or APC) inhibits melanogenesis in B16 melanoma cells in a time-dependent manner without cytotoxicity. In this study, the global gene expression profile of B16 melanoma cells treated with APC extract was determined in order to gain an understanding of the possible mechanisms of action of APC. The results suggest that APC extract inhibits melanin biosynthesis by down-regulating microphthalmia-associated transcription factor (Mitf) and its downstream signaling pathway through JNK signaling activation, and the inhibition of Wnt/β-catenin and cAMP/PKA signaling pathways. APC extract also prevented the transport of melanosomes by down-regulating Rab27a expression. These results suggest that APC may be an important natural skin whitening product and pharmacological agent used for clinical treatment of pigmentary disorders.

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Cell adhesion in a dynamic flow system as compared to static system. Glycosphingolipid-glycosphingolipid interaction in the dynamic system predominates over lectin- or integrin-based mechanisms in adhesion of B16 melanoma cells to non-activated endothelial cells.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)41921-7 ◽

1992 ◽

Vol 267 (24) ◽

pp. 17264-17270

Author(s):

N Kojima ◽

M Shiota ◽

Y Sadahira ◽

K Handa ◽

S Hakomori

Keyword(s):

Endothelial Cells ◽

Cell Adhesion ◽

Dynamic System ◽

Flow System ◽

Melanoma Cells ◽

B16 Melanoma ◽

Static System ◽

Dynamic Flow ◽

B16 Melanoma Cells

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Effect of Phlorotannins Isolated From Eisenia bicyclis on Melanogenesis in Mouse B16 Melanoma Cells

Natural Product Communications ◽

10.1177/1934578x211019264 ◽

2021 ◽

Vol 16 (5) ◽

pp. 1934578X2110192

Author(s):

Yuki Ohno ◽

Shiori Kondo ◽

Kiho Tajima ◽

Toshiyuki Shibata ◽

Tomohiro Itoh

Keyword(s):

Melanoma Cells ◽

B16 Melanoma ◽

Physiological Effects ◽

Related Protein ◽

Eisenia Bicyclis ◽

Melanin Production ◽

Melanocyte Stimulating Hormone ◽

B16 Melanoma Cells ◽

Anti Cancer ◽

Tyrosinase Related Protein

Phlorotannins isolated from brown algae, such as Eisena bicyclis, have positive physiological effects, including anti-cancer, anti-inflammatory, and anti-Alzheimer’s disease. Although phlorotannins have been shown to inhibit tyrosinase, an enzyme essential for melanogenesis, their effect on melanogenesis remains unexplored. Thus, we isolated phlorotannins from E. bicyclis and examined their effects on α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis in murine B16 melanoma cells. Both fucofuroeckol-A (FF-A) and phlorofucofuroeckol-A (PFF-A) suppressed α-MSH-induced melanogenesis. Neither inhibited human tyrosinase (TYR) activity, but both inhibited tyrosinase-related protein-2 activity. FF-A downregulated the expression of microphthalmia-associated transcription factor and TYR, which subsequently suppressed melanin production. These results suggest that phlorotannins could be beneficial as melanin control drugs for hyperpigmentation disorders.

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