ISSN:
1432-069X
Keywords:
Key words In vitro aging
;
Fibroblasts
;
Type I collagen
;
TGFβ
;
TGFβ receptors
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Previous studies have demonstrated that the expression of type I collagen, the most abundant protein in the dermis, is reduced in in vitro-aging fibroblast cultures, but the mechanism controlling the reduction of type I collagen expression is not understood. Recent studies, however, have demonstrated that transforming growth factor β (TGFβ) plays an important role in the regulation of type I collagen expression. The purpose of this study was to investigate the role of TGFβ in downregulation of type I collagen expression in in vitro-aged fibroblasts. We compared the expression of mRNA for α1(I) collagen, TGFβ ,TGFβ type I receptor and TGFβ type II receptor in early- and late-passage fibroblasts by Northern blot hybridizations. The mRNA levels of α1(I) collagen, TGFβ, and TGFβ receptors I and II in late-passage fibroblasts were reduced to 62%, 62%, 59% and 59%, respectively, of those in early-passage fibroblasts. We also compared TGFβ receptor binding in early- and late-passage fibroblasts using receptor binding assays. The affinity of 125 I-TGFβ in late-passage fibroblasts was lower than that in early-passage fibroblasts. These results suggest that the reduction of type I collagen expression in in vitro-aged fibroblasts is regulated by reduced expression of TGFβ and TGFβ receptors I and II and by decreased TGFβ receptor binding ability of the fibroblasts.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004030050282
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