The processes of aging and photoaging are associated with an increase in cellular oxidation. This may be in part due to a decline in the levels of the endogenous cellular antioxidant coenzyme Q10 (ubiquinone, CoQ10). Therefore, we have investigated whether topical application of CoQ10 has the beneficial effect of preventing photoaging. We were able to demonstrate that CoQ10 penetrated into the viable layers of the epidermis and reduce the level of oxidation measured by weak photon emission. Furthermore, a reduction in wrinkle depth following CoQ10 application was also shown. CoQ10 was determined to be effective against UVA mediated oxidative stress in human keratinocytes in terms of thiol depletion, activation of specific phosphotyrosine kinases and prevention of oxidative DNA damage. CoQ10 was also able to significantly suppress the expression of collagenase in human dermal fibroblasts following UVA irradiation. These results indicate that CoQ10 has the efficacy to prevent many of the detrimental effects of photoaging.

Arylsulfatase A polypeptides were examined in cultured fibroblasts from a patient with juvenile metachromatic leukodystrophy and three patients with the adult form of the disease, with the aid of metabolic labeling and immunoprecipitation. The mutant cells were severely deficient in the arylsulfatase polypeptides. The apparent rate of synthesis, however, as estimated from the secretion of polypeptides or activity by cells incubated in the presence of 10 mM NH4Cl was 20-50% of control. In the absence of NH4CI, the mutant enzyme was rapidly degraded upon transport into lysosomes. In the presence of inhibitors of thiol proteinases arylsulfatase A polypeptides were partially protected from degradation, and the catalytic activity of arylsulfatase A was increased. In addition, the treatment partially corrected the capacity of the cells to degrade cerebroside sulfates. Inhibitors of thiol proteinases may be of therapeutic value in variants of metachromatic leukodystrophy, in which an unstable arylsulfatase A is synthesized.Metachromatic leukodystrophy (MLD) comprises several genetic diseases characterized by an intralysosomal storage of cerebroside sulfates, the natural substrates of the lysosomal enzyme arylsulfatase A. Progressive neurological degeneration is the prominent clinical feature in MLD, which is subdivided into the more common late infantile forms and the less common juvenile and adult forms. Each form is deficient in arylsulfatase A and appears to be genetically distinct (for review see refs. 1 and 2). In rare cases presenting clinically as the juvenile form, arylsulfatase A is normal, but there is a deficiency in its activator protein (3). Arylsulfatase A is one of several sulfatases missing in multiple sulfatase deficiency (1). The primary defect in this disease is not known.Lysosomal enzymes are synthesized as larger precursors and subsequently processed to smaller forms (4). Two allelic precursors of arylsulfatase A with apparent Mrs of 62,000 and 59,000 are synthesized in cultured human skin fibroblasts. These precursors are processed to mature forms, which are smaller by a Mr of about 1,500 (5, 6). Both absence and presence of arylsulfatase A polypeptides were found in fibroblasts from patients with late infantile MLD (5, 7). In the present study we have examined the synthesis and processing of arylsulfatase A in fibroblasts of patients with the juvenile and adult forms of MLD. We found that arylsulfatase A was synthesized in these fibroblasts but rapidly degraded when transported into lysosomes. (controls, 8.2-28.1 milliunits/mg of cell protein) and overlapped with the range of activity in late infantile MLD fibroblasts (0.9-1.7 milliunits/mg of cell protein). In agreement with a previous report (1), the residual arylsulfatase A activity in the mutant cells was not, or only to small extent (less than 0.15 milliunits/mg of cell protein), precipitable with antiserum. The cells were maintained in culture as described (13).Labeling of Cells. Confluent cultures in 25-cm2 flasks were washed twi...

Fibroblasts from patients with multiple sulfatase deficiency were analyzed for activities of arylsulfatase A and B, iduronate 2-sulfatase and sulfamatase. A group of patients (group I) severely deficient in all sulfatases (residual activities 5 10% of control) were differentiated from patients (group 11) with residual sulfatase activities of up to 90% of control. The synthesis and stability of arylsulfatase A and B were determined in pulse-chase labelling experiments. The apparent rate of synthesis of arylsulfatase A and B varied from 30% to normal in both fibroblasts from group I and I1 multiple sulfatase deficiency. In group I the molecular activity of the arylsulfatase A and B was more than 10-fold lower than in control fibroblasts. In group I1 the molecular activity of the arylsullatase A was twofold to threefold lower and that of arylsulfatase B half of normal. In fibroblasts of both groups the stability of arylsulfatase A polypeptides was significantly diminished. For arylsulfatase B the instability was restricted to the mature 47000-M, polypeptide and was variable within both groups. These results demonstrate that multiple sulfatase deficiency is a heterogeneous disorder, in which the primary defects can impair both the catalytic properties and the stability of sulfatases.Multiple sulfatase deficiency (MSD) is a lysosomal storage disorder biochemically characterized by a partial deficiency in activities of at least six lysosomal sulfatases and one nonlysosomal sulfatase [I] (for recent reviews see [2, 31). The residual activities of the sulfatases are highly variable among fibroblasts from different patients and dependend greatly on culture variables [4,5]. The mutations in MSD and in several single sulfatase deficiency disorders (e. g. metachromatic leukodystrophy, mucopolysaccharidosis type 11, IIIA and IV) are non-allelic [6-81. The stability of arylsulfatase A in MSD fibroblasts is severely decreased. This suggested that the primary defect in MSD is related to a gene product conferring stability on sulfatases [9].The present study reports the classification of MSD fibroblasts into two groups according to residual sulfatase activities and on the synthesis, processing and stability of arylsulfatase A and B in MSD fibroblasts of the two groups. MATERIALS AND METHODS[~-~~S]Methionine (specific activity 950 -1200 Ci/mmol) and I4C-methylated standards were from New England Nuclear, Dreieich. p-Nitrocatechol sulfate was from Sigma, Miinchen. Immuno-Precipitin (a 10% suspension of Stuphylococcus aureus cell walls) was from Bethesda Research Laboratory, Neu-Isenburg. Ultrafiltration was performed in ultrathimbles UH 25/10 from Schleicher & Schull, Dassel. Cell cultureHuman diploid fibroblasts were maintained at 37°C in 5% C 0 2 in Eagle's minimal essential medium supplemented [13] were isolated from extracts of cells and medium as described. Alternatively the extracts were incubated for 30 min with y5 vol. of Immuno-Precipitin and centrifuged for 1 h at 45000xg. The supernatant was adjusted to 1 YO Triton X-...

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Continuous and sinusoidal endothelial cells display marked morphological and functional heterogeneity as to their plasmalemmal vesicle content, to the kind of intercellular junctional complexes, to the existence and kind of fenestrae and gaps, to the existence and character of their basement membrane, to their ability for phagocytosis and to other functional parameters. Monoclonal antibody 1F10, raised against human umbilical vein endothelial cells (HUVE cells), reflects these differences in recognizing – without any nonendothelial side reactions – an endothelial cell surface antigen, abundantly expressed in continuous endothelia, low and inconsistently expressed in liver sinusoidal and dermal lymphatic endothelia and absent from splenic sinusoidal endothelial cells. In differentiated skin vascular tumors, 1F10 antigen is expressed in normal amounts while it is only low and inconsistently expressed in the dedifferentiated endothelial cells of Kaposi’s sarcoma and hemangiosarcoma. HUVE cells in culture, in contrast to their in situ ancestors, express variable amounts of 1F10 antigen. When endothelial cell-conditioned medium (ECC medium) is supplied to HUVE cells in culture, no 1F10 antigen is expressed, while supplementation with fresh serum-containing medium (FSC medium) or cytokines, such as bFGF, suffices to maintain 1F10 expression in 10–70% of the cells. From this we conclude that developmental regulation, environmental influences and cytokine supply contribute to the differentiation and maintenance of the 1F10⁺ and 1F10^- endothelial cell phenotypes, both in vivo and in vitro.