The good and the bad collagens of fibrosis – Their role in signaling and organ function

Improvement of non‐invasive markers of NAFLD from an individualised, web‐based exercise program

“…Hepatic fibrosis is characterised by accumulation of excess extracellular matrix (ECM) and non‐invasive biomarkers of collagen turnover have been correlated with histological changes. Activated types of fibroblasts produce type III collagen in a dense interstitial matrix, which may be quantified by the N‐terminal pro‐peptide of type III collagen (PIIINP) PRO‐C3. PRO‐C3 is released into serum during ECM formation and has emerged as a non‐invasive biomarker of fibrogenesis, correlating with the severity of liver fibrosis in NAFLD by itself and in compound surrogate scores, as well as being prognostic for fibrosis progression .…”

Is the Total Amount as Important as Localization and Type of Collagen in Liver Fibrosis Attributable to Steatohepatitis?

“…This is particularly important, because collagens are not just collagens in the sense of being inert structural rods. In fact, most collagens contain only a minor proportion of rigid collagen domains, but are rather made of interrupted triple helices and larger noncollagenous domains, which render them flexible and endow them with multifunctional properties (e.g., in cellular interactions) . At present, 28 different collagens have been identified in the collagen superfamily, with 46 genetically distinct collagen chains.…”

“…At present, 28 different collagens have been identified in the collagen superfamily, with 46 genetically distinct collagen chains. Each of these collagen molecules is unique with respect to its structural and signaling properties, its interaction with other ECM components, and regarding its localization in the diseased organs (Fig. ).…”

“…It contains also other important collagens, such as the fibril associated collagens type XII and XIV, and the fibril‐connecting micro‐filamentous type VI collagen that, when disturbed, may signal danger . The fibrillar collagens are very different from the networking collagens, forming a dense diffusion barrier meshwork, and are central to tissue structure and integrity …”

Suppression of hepatic fibrosis by efficient Col1a1 silencing using shRNA inducible mouse models

“…Types I, III, IV, V, and VI collagens are major constituents of both the normal and fibrotic liver. Each collagen is made up of three identical or genetically different alpha chains.There are other more recently identified collagens that constitute the liver ECM in health and especially in disease (8,10).…”