Type I and Type III collagen (COL1/COL3)

Type I and Type III collagens are the primary fibrillar components of the human extracellular matrix, providing essential structural support and tensile strength to tissues such as skin, bone, tendons, and internal organs (UniProt P02452, P02461). Type I collagen is the most abundant, particularly in bone and mature scars, while Type III collagen is prevalent in elastic tissues like blood vessels and is often the first collagen deposited during early wound healing (StatPearls, Collagen Synthesis). In many chronic diseases, the dysregulated overproduction and accumulation of these collagens lead to fibrosis, resulting in organ stiffness and eventual failure (NCBI, Role of Collagen in Fibrosis). Therapeutic interventions target these proteins through various mechanisms, including the inhibition of collagen-producing myofibroblasts, the prevention of collagen cross-linking, and the direct enzymatic degradation of collagen deposits (FDA, Xiaflex Label). Monitoring these collagens is clinically significant, as fragments like PIIINP and PINP serve as vital biomarkers for disease progression in conditions like liver cirrhosis and idiopathic pulmonary fibrosis. Consequently, Type I and Type III collagens represent central targets in the development of anti-fibrotic and regenerative therapies.

Other names

Fibrillar collagenCollagen alpha-1(I) chainCollagen alpha-1(III) chainType I collagenType III collagenCOL1A1COL1A2COL3A1

Drugs targeting Type I and Type III collagen act by inhibiting synthesis via TGF-beta or PDGF pathway modulation, preventing post-translational folding (e.g., HSP47 inhibition), blocking extracellular cross-linking (e.g., LOXL2 inhibition), or directly inducing enzymatic degradation of collagen fibers.