Increased Diameters of Collagen Fibrils Precipitatedin vitroin the Presence of Decorin from Various Connective Tissues

Abstract

Proteoglycans were isolated from bovine skin, sclera, deep flexor tendon and the periphery of the temporomandibular joint disc with urea. Decorin was purified from each of these extracts by ion-exchange, hydrophobic-interaction and gel-filtration chromatography. Purities were assessed by amino acid analysis and by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) of the protein cores released by digestion with chondroitin-ABC-lyase. In these respects the decorins were indistinguishable. However the glycosaminoglycan chains released by digesting the proteoglycans with papain varied widely in mobility on SDS-PAGE: that from skin decorin migrating fastest and that from tendon decorin slowest. The effects of each of the decorins on collagen fibrillogenesis in vitro were similar, all reducing the rate of fibril growth (by 55 to 71%, depending on the source of the proteoglycan) and increasing the diameters of the fibrils formed (by 27 to 66%). Core protein alone, isolated from skin decorin, reduced the rate of fibril growth as effectively as intact decorin, but had no effect on the diameter of fibrils formed. The dermatan sulphate chain and the protein thus appear to play different roles in the interaction of intact decorin with collagen. These data suggest that decorin found in fibrous connective tissues may increase Type I collagen fibril diameters, resulting in tissues that are better able to withstand tensile forces.

Local Expression of Bovine Decorin by Cell-Mediated Gene Transfer Reduces Neointimal Formation After Balloon Injury in Rats

“…42 However, other reports now suggest that decorin can also affect collagen fiber formation and arrangement in various ways. Decorin was recently shown to improve the tensile properties of collagen fibers 43 and to increase fibril diameter 17 in vitro. In vivo, decorin is frequently found to be closely associated with collagen and is thought to control collagen fiber formation and arrangement, in particular, the interfibrillar spacing (for review see Reference 44).…”

“…10 Decorin was chosen for the present study because it has previously been shown to inhibit TGF-␤ 1 -induced ECM accumulation in a glomerulonephritis model in rats 11 and a lung fibrosis model in rabbits, 12 to inhibit proliferation of various cell types, [13][14][15][16] and to affect collagen fiber formation. 17,18 In the present study, we used cell-mediated transfer of the decorin gene to achieve local overexpression of bovine decorin in the neointima that develops after balloon injury of the rat carotid artery. We demonstrate that the local overexpression of this ECM molecule reduces intimal thickening in response to…”

Expression of decorin and collagens I and III in different layers of human skin in vivo: a laser capture microdissection study

“…The presence of proteoglycans at the fibril surface correlates with the expansion of fibril diameters to an ideal size, possibly implicating decorin influence in both fusion and assembly of collagen bundles in vivo (Scott 1988;Kuc and Scott 1997). Since decorin non-covalently binds to the surface of fibrillar collagens, it could be assumed that a strong correlation between decorin expression and the extensive matrix assembly in reticular dermis exists (Danielson et al 1997).…”

Biochemical and Cytochemical Characterization of Extracellular Proteoglycans in the Inner Circular Smooth Muscle Layer of Dog Small Intestine

“…The collagen associated proteodermatan sulfate in the inner smooth muscle layer presumably represented decorin. Decorin is always associated with collagen fibrils in the matrix of different tissues, thought to play a role in the control of fibrillogenesis and in the organization of collagen fibrils into larger fibrils (30,31). Decorin has been observed in the perimysium and endomysium of skeletal muscle (32).…”