Epidermal lysosomes. Electron microscopic-cytochemical studies

Wolff, K.

doi:10.1001/archderm.101.3.276

Cited by 20 publications

(19 citation statements)

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“…Moreover, fl-glucosidase levels are lower in oral mucosa than in the epidermis of the same species ( 19). Whereas fl-glucosidase activity has been quantitated previously in a number of epidermal preparations (20)(21)(22)(23)(24)(25)(26)(27), we recently demonstrated that the bulk ofthis activity is fl-glucocerebrosidase (f3-GlcCer'ase) and that it is localized largely to the outer epidermis and stratum corneum ( 1 1). Although these prior studies suggest that extracellular processing ofglycosphingolipids may be important for the development of barrier integrity, proof of this hypothesis has been lacking.…”

Section: Introductionmentioning

confidence: 94%

Processing of epidermal glucosylceramides is required for optimal mammalian cutaneous permeability barrier function.

Holleran¹,

Takagi²,

Menon³

et al. 1993

J. Clin. Invest.

245

201

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The interstices of the mammalian stratum corneum contain lipids in a system of continuous membrane bilayers critical for the epidermal permeability barrier. During the transition from inner to outer stratum corneum, the content of polar lipids, including glucosylceramides, decreases while ceramide content increases. We investigated whether inhibition of glucosylceramide hydrolysis would alter epidermal permeability barrier function. Daily topical applications of bromoconduritol B epoxide (BrCBE) to intact murine skin selectively inhibited fl-glucocerebrosidase, increased glucosylceramide content of stratum corneum with ceramide content remaining largely unchanged, and caused a progressive, reversible decrease in barrier function. Histochemistry of inhibitor-treated epidermis revealed persistence of periodic acid-Schiff-positive staining in stratum corneum cell membranes, consistent with retention of hexose moieties. Electron microscopy of inhibitor-treated samples revealed no evidence of toxicity or changes in the epidermal lipid delivery system. However, immature membrane structures persisted in the intercellular spaces throughout the stratum corneum, with reappearance of mature membrane structures progressing outward from the lower stratum corneum upon termination of BrCBE. Finally, the induced barrier abnormality was not reversed by coapplications of ceramide. These data demonstrate that glucosylceramide hydrolysis is important in the formation of the epidermal permeability barrier, and suggest that accumulation of glucosylceramides in stratum corneum intercellular membrane domains leads to abnormal barrier function. (J. Clin. Invest. 1993.91:1656-1664

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Section: Introductionmentioning

confidence: 94%

Processing of epidermal glucosylceramides is required for optimal mammalian cutaneous permeability barrier function.

Holleran¹,

Takagi²,

Menon³

et al. 1993

J. Clin. Invest.

245

201

View full text Add to dashboard Cite

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“…LG components include glucosylceramides (GlcCer) and other lipids (Madison et al, 1998), various hydrolytic enzymes, such as proteases, acid phosphatases, glucosidases, and lipases (Wolff and Schreiner, 1970;Hayward, 1979;Traczyk, 1983, 1985;Grayson et al, 1985;Madison et al, 1998), and other proteins including corneodesmosin (Cdsn) (Serre et al, 1991). LG have been observed by electron microscopy as round or oblong, membrane-delimitated, lamellate organelles (Hayward, 1979;Odland and Holbrook, 1981;Landmann, 1988).…”

mentioning

confidence: 99%

Epidermal Lamellar Granules Transport Different Cargoes as Distinct Aggregates

Ishida‐Yamamoto

Simon

Kishibe

et al. 2004

Journal of Investigative Dermatology

138

113

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Lamellar granules (LG) of the epidermis appear as discrete round or oblong shaped granules in classical transmission electron micrographs, but a recent cryo-transmission electron microscopy study has claimed that LG are in fact branched tubular structures. LG contain various cargoes including lipids, hydrolytic enzymes, and several other proteins. It is not known whether there are any differences in the timing of expression among them and whether they are sorted into the granules individually or collectively. In order to address these questions, we studied the expression of glucosylceramides (GlcCer), cathepsin D (CatD), corneodesmosin (Cdsn), kallikrein (KLK)7, and KLK8 in normal human epidermis using confocal laser scanning microscopy and immunoelectron microscopy. The results were consistent with the model that LG are parts of a branched tubular structure. In this structure, all the components were shown to be distributed as separate aggregates. In the trans-Golgi network (TGN), bulbous protrusions containing GlcCer, Cdsn, KLK7 and KLK8, and small CatD-positive vesicles were observed. The molecules were shown to be delivered to the apical region of granular keratinocytes. This study provides strong evidence for the sequential synthesis and independent trafficking of various LG cargoes, including for the first time CatD and KLK8, from TGN.

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“…Morphological studies [29,30,33,41] and observations on the enzymatic reactivity of the MCGs [31,33,42] suggest that MCGs are composed at least of the following constituents: free lipids with high amounts of sphingolipids (glucosylceramide and ceramide), small quantities of other polar (cholesterol sulfate) and nonpolar (triglycerides, cholesterol esters, hydrocarbons) lipid species [11], and free sterols and fatty acids [19,24,39]. Among the sphingolipids one of the seven different types identified so far has been found predominantly in MCGs: O-acylglucosylceramide [24].…”

Section: Biochemistry Of the Mcgsmentioning

confidence: 99%

Liposomes for atopic dry skin: the rationale for a promising approach

Schmid

Korting

1993

Clin Investig

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Atopic dry skin characterized by a defect of the barrier function as determined by transepidermal water-loss measurements at the ultrastructural level shows an increase in membrane-coating granules (MCGs). MCGs are lamellar, ovoid organelles appearing in the stratum spinosum and stratum granulosum. MCGs consist of stacks of small parallel disks that are extruded and fuse to continuous lamellae. Liposomes, i.e., unior multilamellar vesicles composed of alternating lipid and water phases are structurally similar. Moreover, they also can form continuous lamellae. While phospholipids are generally used for liposome production, skin lipids and in particular ceramides can also be used. These lipids also seem to be the major components of MCGs. Hence, it seems advisable to use liposomes made of such lipids in the treatment of atopic dry skin. Apart from the probable inherent effect liposomes of this type may also apply particularly well for the delivery of active components.

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Epidermal lysosomes. Electron microscopic-cytochemical studies

Cited by 20 publications

References 0 publications

Processing of epidermal glucosylceramides is required for optimal mammalian cutaneous permeability barrier function.

Processing of epidermal glucosylceramides is required for optimal mammalian cutaneous permeability barrier function.

Epidermal Lamellar Granules Transport Different Cargoes as Distinct Aggregates

Liposomes for atopic dry skin: the rationale for a promising approach

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