Insight into the Regulatory Function of Human Hair Keratins in Wound Healing Using Proteomics

Keratins derived from human hair possess excellent wound healing qualities. However, their functional contribution to this process is poorly understood. In this study, the regulatory function of human hair keratins in wound healing is investigated using proteomic analysis by dividing keratins into different groups based on their molecular weight distributions: low molecular weight keratins (LMWK, 10–30 kDa), medium molecular weight keratins (MMWK, 30–50 kDa), and high molecular weight keratins (HMWK, >50 kDa). Keratin hydrogels with different molecular weights exhibit various morphologies, rheological properties, degradation rates, and wound healing activities. Using proteomic analysis, LMWK and HMWK hydrogels exhibit a stronger regulatory ability for wound healing at days 1 and 7, respectively. The major functions of LMWK during wound healing are regulation of cells communication and function. In contrast, proteins associated with energy metabolism are significantly expressed after HMWK hydrogel treatment at day 1, and these play an important role in cellular growth and reactive oxygen species scavenging at day 7. These results demonstrate that the wound healing qualities of human hair keratins are influenced by their molecular weight distribution, and the proteomic analysis sheds new light on the regulatory function of human hair keratins during wound healing.