Molecular weight-controllable oral yak skin collagen for enhanced healing of photoaged skin

Photoaging skin caused by excessive UV radiation has been one of the most common skin diseases, leading to wrinkles, hyperpigmentation, inflammation, and even skin cancer. Oral collagen supplements have emerged as a potential strategy for photoaged skin; however, they suffer from unclear molecular weights and high risk of disease transmission. Herein, we have for the first time developed a series of molecular weight-controllable oral yak skin collagen (OYC) by the molecular weight-directed enzymolysis-chromatography combined strategy. Toxicological studies indicated that OYC displayed good biocompatibility and no organ toxicity. Combo evaluations revealed that OYC contributed to the restoration of photoaged skin to healthy levels. Histological analysis demonstrated that OYC improved the histopathological changes, significantly accelerating the regeneration of collagen fibers. Antioxidant indicators analysis further indicated that OYC alleviated oxidative stress induced by UV irradiation. Notably, OYC with medium molecular weight (MOYC) exhibited the most effective anti-photoaging properties, likely due to its exceptional ability to scavenge reactive oxygen species, improved intestinal absorption, and optimal resistance to degradation. This orally administered yak skin collagen provides a new strategy and theoretical basis for the prevention and treatment of photoaged skin, offering broad prospects in the fields of nutritional supplements and skincare products.

Graphical Abstract