Injection of Different Concentrations of Recombinant Humanized Type III Collagen Into the Dermis Promotes Type III and Type I Collagen Deposition as Well as Angiogenesis: An In Vivo Study

Type III recombinant humanized collagen (rhCol III) has a promising future in cosmetic applications. To investigate the histological changes associated with injection of different concentrations of Type III rhCol III into the dermis. Twenty mice were divided into a control, low-dose (LD) group, and high-dose (HD) group. The animals were euthanized 1, 2, 3, and 4 weeks after the injection. Injections of rhCol III induced an increase in collagen formation in a concentration-dependent manner. Type I collagen (Col I) was upregulated in both HD and LD groups to varying extents, often similar to that of Col III. Fibroblast proliferation plays an important role in the deposition of Col I and Col III. Injections of rhCol III promoted angiogenesis at later stages, regardless of concentration dependency. Intradermal injections of rhCol III can promote fibroblast proliferation, enhancing the deposition of both Col I and Col III, and stimulating angiogenesis. Further studies are required to elucidate the mechanisms.