Some aspects of the modulation and regulation of collagen synthesis in vitro

Abstract

We reviewed here a number of publications containing data on the quantitative aspects of collagen synthesis in vitro. In one section we discussed the factors which modulate the amount of collagen synthesized in various culture systems and in another section we presented experimental evidence for regulatory mechanisms operating in collagen synthesis on the transcriptional and/or translational levels. We believe that growing knowledge of the mechanisms controlling collagen synthesis will help us to understand and deal with fibrotic processes better.

Low rate of procollagen conversion in dermatosparactic sheep fibroblasts is paralleled by increased synthesis of type I and type III collagens.

“…Normal cells had their highest capacity for collagen synthesis (-40o) at the early phase of the cultures, and this synthesis decreased to 2-317 under multilayer conditions (Figure 2b). These values are in good agreement with previous reports on collagen synthesis by normal fibroblasts in vitro (reviewed by Muller et al, 1981). Quantitation of the total incorporation of radioactivity into protein and of dialysable hydroxyproline, as a measure of degradation of newly synthesized procollagen, showed similar values of -30%7o degraded collagen for both affected and normal cell cultures.…”

Studies on collagen metabolism in the Marfan syndrome

“…Depending on the method of evaluation and cell culture conditions (i.e. cell density) the values obtained for the type 111: type I ratio varied from 5 to 25% for both Marfan and control fibroblasts [29]. On gel electrophoresis no evidence for any structural abnormality of the type 111 collagen chains was seen (Fig.…”

“…cell density) the values obtained for the type 111: type I ratio varied from 5 to 25% for both Marfan and control fibroblasts [29]. The peak eluting between al(1) and a2(I) on the latter was rechromatographed twice on an agarose column, first under non-reducing and then under reducing condi- tions, in order to verify that only al(II1) chains were eluted in this position (not shown).…”

Effect of Force Level on Synthesis of Type III and Type I Collagen in Mouse Interparietal Suture

“…Collagen is the main constituent of fibrous joints, and its synthesis and secretion by fibroblasts constitute a tightly controlled process under constant influence of extracellular conditions (Hance and Crystal, 1977;Muller et al, 1981;Saltzman et al, 1982), including the immediate mechanical environment (Leung et al, 1976(Leung et al, , 1977Yen et al, 1980Meikle et al, 1982;Miyaki and Forbes, 1987;and Southard and Forbes, 1988). Much evidence suggests that mechanical perturbation of the plasma membrane of connective tissue cells initiates specific biochemical changes within the cell (Rodan et al, 1975;Bourret and Rodan, 1976;Hang et al, 1976;Norton et al, 1977;Somjen et al, 1980).…”