ascorbic-acid and Scleroderma--Localized

Topics: Analysis of Variance; Antioxidants; Ascorbic Acid; Cholesterol; Chromatography, High Pressure Liquid; Humans; Lipids; Lipoproteins, HDL; Lipoproteins, LDL; Scleroderma, Localized; Scleroderma, Systemic; Triglycerides; Vitamin E

Scleroderma is a fibrotic disorder of unknown etiology that is characterized by excessive collagen synthesis and its deposition in the skin and various internal organs.. To examine whether an overproduction of extracellular matrix molecules is a result of either increased fibroblast proliferation or increased collagen synthesis. As results of clinical trials with 1,25-dihydroxyvitamin D3 (calcitriol) have suggested beneficial effect in the treatment of scleroderma patients, the effects of calcitriol on fibroblasts derived from scleroderma and normal skin has been examined as well.. Cultures of fibroblasts were established from biopsies from involved and uninvolved skin of scleroderma patients and from skin of healthy subjects, and compared with respect to proliferation, collagen synthesis and collagen lattice contraction.. No significant differences in cell proliferation and in the extent of fibroblast-induced collagen lattice contraction have been found between scleroderma patients exhibited a disorganized growth pattern in a monolayer culture in contrast to normal fibroblasts. Collagen synthesis tends to be higher in scleroderma fibroblasts as compared with controls. Calcitriol exerted an antiproliferative and antisynthetic effect on fibroblasts, which, however, did not discriminate healthy fibroblasts from fibroblasts derived from involved or uninvolved scleroderma plaques.. Our findings suggest that collagen accumulation may not result from increased proliferation or altered dynamic properties of fibroblasts in a scleroderma lesion but from increased collagen biosynthesis. We additionally found that calcitriol does not selectively affect scleroderma fibroblasts.

Topics: Adult; Aged; Ascorbic Acid; Biopsy; Calcitriol; Carbon Radioisotopes; Cell Division; Cells, Cultured; Collagen; Dose-Response Relationship, Drug; Extracellular Matrix; Female; Fibroblasts; Humans; Male; Middle Aged; Proline; Scleroderma, Localized; Scleroderma, Systemic; Skin

The synthesis of collagen and its deposition into the extracellular matrix were studied in scleroderma and normal skin fibroblast cultures using immunocytochemistry, electron microscopy and electrophoretic analysis. Indirect immunofluorescence localized type I collagen to intracellular granules of normal skin fibroblasts but not to the extracellular matrix. A 48-h ascorbic acid-treatment of scleroderma and normal skin fibroblasts induced the appearance of fibrillar, collagen-containing deposits in the extracellular space as indicated by indirect immunofluorescence and electron microscopy. Interestingly, similar type I collagen-containing fibrils were observed in cultures of scleroderma skin fibroblasts even without preceding ascorbic acid treatment. Electrophoretic analysis revealed that ascorbic acid increases the conversion of procollagen to collagen to same extent both in scleroderma and control cell layers. The accumulation of collagen to the cell layer of scleroderma fibroblasts was increased when compared to normal skin fibroblasts; whereas the relative conversion of procollagen to collagen was identical in scleroderma and normal fibroblasts. The results show that the conversion of procollagen to collagen in the cell layers of both scleroderma and normal skin fibroblasts is dependent on ascorbic acid, due to improved secretion of procollagen molecules in the presence of ascorbic acid.

Topics: Ascorbic Acid; Cells, Cultured; Collagen; Extracellular Matrix; Female; Fibroblasts; Humans; Middle Aged; Scleroderma, Localized