Fibromodulin

Fibromodulin is a 42 kDa collagen-binding keratan sulfate SLRP (small interstitial leucine-rich repeat proteoglycans) expressed in connective tissue and cartilage. It shares a significant sequence homology with other proteoglycans such as biglycan and decorin (Iozzo RV et al (2015). Fibromodulin binds to collagen, regulates (inhibits) collagen fibrillogenesis of collagen types I and III and collagen cross-linking. Furthermore, fibromodulin regulates TGF-beta activities by binding TGF-beta into the extracellular matrix.

FMOD expression is increased in inflammatory, fibrotic and wound healing processes in liver, kidney, lung and skin. It decreases with age so that non-glycated forms of fibromodulin can accumulate in tissues such as cartilage (Kalamajski S et al. 2010).

In scars FMOD regulates fibrotic reactions by interacting with the transforming growth factor (TGF) beta.

1. Iozzo RV et al (2015) Proteoglycan form and function: a comprehensive nomenclature of proteoglycans. Matrix Biol 42:11-55.
2. Karamanos NK (2017) Matrix pathobiology-central roles for proteoglycans and heparanase in health and disease. The FEBS journal 284:7-9.
3. Kalamajski S et al (2010) The role of small leucine-rich proteoglycans in collagen fibrillogenesis. Matrix Biol 29:248-253.
4. Lunde IG et al (2016) Syndecans in heart fibrosis. Cell Tissue Res 365(:539-552.