Fibrillar Collagen: A Review of the Mechanical Modeling of Strain-Mediated Enzymatic Turnover

Abstract

Abstract Collagen is the most abundant protein in mammals, often serving as the main load bearing constituent in soft tissues. Collagen undergoes continuous remodeling processes in which present collagen degrades, and new collagen is formed and deposited. Experiments find that modestly strained fibrillar collagen is often stabilized to enzymatic degradation, a mechanism that is essential in approaching and maintaining a homeostatic balance in the tissue remodeling process for healthy tissue. At larger strains, this decline in the collagen degradation rate may be reversed. This article reviews different modeling approaches that seek to account for the effect of straining on collagen remodeling, both with respect to collagen amount and to resulting mechanical properties. These models differ in the considered length scale starting from the molecular scale up to the larger continuum scale.