Cultured psoriatic fibroblasts from involved and uninvolved sites have a partial but not absolute resistance to the proliferation-inhibition activity of 1,25-dihydroxyvitamin D3.
AUTOR(ES)
MacLaughlin, J A
RESUMO
We examined the responsiveness of cultured dermal fibroblasts from biopsies of uninvolved and involved areas of skin from six patients with psoriasis to the cell-proliferation-inhibition activity of 1,25-dihydroxyvitamin D3 (1,25-(OH)2-D3). Cultured fibroblasts from age-matched controls responded to 1,25-(OH)2-D3 (at 0.01, 1, 10, and 100 microM) in a dose-dependent fashion, whereas cultured psoriatic fibroblasts from involved or uninvolved skin showed no inhibition of proliferation when exposed to 0.01 or 1 microM of 1,25-(OH)2-D3. However, 1,25-(OH)2-D3 did inhibit proliferation of cultured psoriatic fibroblasts when the concentrations were increased to 10 and 100 microM. An analysis of the 1,25-(OH)2-D3 receptors in cultured psoriatic fibroblasts from uninvolved skin revealed that the Kd, nmax, and sedimentation coefficient were identical to the receptors found in the fibroblasts from age-matched controls. Therefore, cultured psoriatic fibroblasts from involved and uninvolved skin have a partial resistance to 1,25-(OH)2-D3, suggesting that there may be a biochemical defect that is inherent in the dermal fibroblasts of psoriatic patients. Recognition of this defect may provide a new approach for the evaluation of the cause and treatment of this disfiguring skin disorder.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=390578Documentos Relacionados
- Enterohepatic physiology of 1,25-dihydroxyvitamin D3.
- Identification and regulation of 1,25-dihydroxyvitamin D3 receptor activity and biosynthesis of 1,25-dihydroxyvitamin D3. Studies in cultured bovine aortic endothelial cells and human dermal capillaries.
- Resistance to 1,25-dihydroxyvitamin D. Association with heterogeneous defects in cultured skin fibroblasts.
- DNA sequences in the rat osteocalcin gene that bind the 1,25-dihydroxyvitamin D3 receptor and confer responsiveness to 1,25-dihydroxyvitamin D3.
- 1,25-Dihydroxyvitamin D3 up-regulates the 1,25-dihydroxyvitamin D3 receptor in vivo.