The effect of 0.1-10 microM retinoic acid (RA) on foetal bovine chondrocytes was investigated in high-density cultures (0.6 x 10(6) cells/cm2). After 5 days of culture in ascorbate-free medium, control chondrocytes presented a typical rounded shape and synthesized type II, IX, XI and III collagens. After RA treatment on days 2-5 of culture, the cells exhibited a fibroblast-like shape and decrea...

Nitric oxide (NO) mediates endothelial angiogenesis via inducing the expression of integrin α(v)β(3). During angiogenesis, endothelial cells adhere to and migrate into the extracellular matrix through integrins. Collagen IV binds to integrin α(v)β(3), leading to integrin activation, which affects a number of signaling processes in endothelial cells. In the present study, we evaluated the role o...

Two drugs, D-penicillamine and daunorubicin, were tested for their effect on proliferation and collagen synthesis of cultured conjunctival fibroblasts. This cell type is likely responsible for scar formation and ultimate filter surgery failure in glaucoma patients. Both drugs were antiproliferative; however, D-penicillamine required 2000 times the concentration of daunorubicin to achieve a simi...

In the dermis, vitamin C is required for the formation of hydroxyprolyl residues to form stable triple-helical collagen molecules, and hydroxylysyl residues operating in crosslinks synthesis. In fibroblasts culture, vitamin C is also known to stabilize the collagen messenger RNAs (m-RNA) and increase procollagen synthesis. The activity in the dermis of vitamin C topically applied on normal huma...

Both normal and neoplastic tissues have a stroma comprised of fibroblasts which deposit an extracellular matrix (ECM) enriched in collagen. In most normal tissues, the synthesis and breakdown of the ECM is maintained at a low level. However, in normal adult tissues such as endometrium, and in rapidly growing embryonic and neoplastic tissues, there is a significant increase in the synthesis and/...

THE PURPOSE OF THIS STUDY WAS TO 1) examine the effects of hydroxysafflor yellow A (HSYA) on the proliferation, collagen and cytokine synthesis of vascular adventitial fibroblasts as induced by angiotensin II (Ang II) in normal Sprague-Dawley (SD) rats in vitro, and 2) to assess the effects of HSYA on morphological changes and collagen accumulation of vascular adventitia in spontaneously hypert...

Human glomerular epithelial cells produce matrix material e.g. collagen type IV. In vitro, the synthesis of collagen can be monitored by the incorporation of 3H-proline, a precursor molecule of the collagens. We report on the enhancement of collagen synthesis by glomerular epithelial cells with highly purified or recombinant I1-1. Since I1-1 is released from monocytes or glomerular mesangial ce...

Cotranslational insertion of type I collagen chains into the lumen of the endoplasmic reticulum (ER) and their subsequent folding into a heterotrimeric helix is a complex process which requires coordinated action of the translation machinery, components of translocons, molecular chaperones, and modifying enzymes. Here we describe a role for the protein TRAM2 in collagen type I expression in hep...

Light and electron microscopy of resorbing connective tissues have shown that the collagen fibers and fibrils disappear. It is usually presumed that resorbed collagen is degraded proteolytically to hydroxyproline-containing peptides and to free amino acids, including hydroxyproline. We wish to present evidence that collagen can be resorbed and then reutilized without such breakdown. Urinary exc...

Our morphological studies have demonstrated that the appearance of localized, paired zones of primary calcification on either side of the midline of the 19-d embryonic chick sternum is heralded by the development of paired, translucent zones 2 d previously. Histological studies demonstrated that the majority of chondrocytes within these translucent zones are hypertrophic, and that the zones are...