Periostin is a matricellular protein, i.e. an extracellular matrix protein that interacts both with other ECM proteins and with cell-surface receptors. Like many other matricellular proteins, the function of periostin is important both in embryonic development and in the remodeling of adult tissues in response to pathological insults. Periostin was originally isolated as an osteoblast-specific marker that functions as a cell adhesion molecule for preosteoblasts and is thought to be involved in osteoblast recruitment, attachment and spreading (Kruzynska-Frejtag A. et al., 2004). Periostin has recently been shown to promote collagen fibrogenesis, inhibit differentiation of progenitor cells into cardiomyocytes and to be essential in maintaining the biomechanical properties of the adult myocardium (Norris et al., 2008)
