Recombinant type I & III chimeric collagen significantly enhances the vitality of fibroblasts and decelerates the skin aging process.

Collagen, the most abundant protein in the mammalian extracellular matrix, is critical for skin structure and function, with Type I and Type III collagens being particularly important. Collagen degradation in skin is accelerated by aging and UV exposure, leading to structural and functional impairments. Exogenous collagen supplementation has been shown to restore skin structure and function. Traditional collagen extraction from animal tissues is limited by safety and quality concerns, while recombinant human collagen offers improved safety but faces challenges in solubility and production. This study aimed to construct a chimeric collagen derived from both Type I and Type III collagens and achieve its soluble expression in E. coli. Through translational pausing technology, a recombinant chimeric human collagen containing functional domains of both collagen types was successfully constructed and expressed with a yield of 1.36 g/L. A cysteine-rich C-propeptide domain was fused to enhance assembly and stability. The "dual-function" collagen significantly promoted fibroblast proliferation, migration, and adhesion, while stimulating endogenous Type I and Type III collagen production. Using the C. elegans model, the recombinant protein extended lifespan and enhanced oxidative aging resistance. Skin imaging confirmed its penetration into the dermis, and human skin efficacy tests demonstrated its ability to reduce periorbital wrinkles and crow's feet. This recombinant "dual" human collagen promotes endogenous collagen synthesis, accelerates skin repair, reduces aging signs, and shows no observed side effects, offering promising potential for anti-aging applications.