Keratin-Butyrate Scaffolds Promote Skin Wound Healing in Diabetic Rats Through Down-Regulation of IL-1β and Up-Regulation of Keratins 16 and 17

Impaired wound healing particularly in diabetics creates a significant healthcare burden. The study aimed to evaluate the effect of keratin-butyrate fibers (FKDP +0.1%NaBu) in a full-thickness skin wound model in 30 diabetic rats. Physicochemical examination showed that the obtained dressing possesses a heterogeneous structure and butyrate was slowly released into the wound. Moreover, the obtained dressing is nontoxic and supports cell growth. In vivo results showed that keratin-butyrate dressing accelerated wound healing on days 4 and 7 post-injury (p < .05). Histopathological and immunofluorescence examination revealed that applied dressing stimulated macrophage infiltration, which favors tissue remodeling and regeneration. The dressing was naturally incorporated into regenerating tissue. The highest mRNA expression level of interleukin 1β (IL-1β) was observed during the first 2 weeks in the control wounds compared to FKDP +0.1%NaBu treated wounds, in which IL-1β was significantly decreased. In FKDP +0.1%NaBu dressed wounds, mRNA expression of IL-10 and VEGF increased significantly (p < .05) from day 14. Keratin-butyrate treated wounds enhanced mRNA expression of keratin 16 and 17 and zonula occludens protein-1 and junctional adhesion molecules (p < .05) on days 14, 21, and 28 post-injuries. Our study showed that keratin butyrate dressing is safe and can efficiently accelerate skin wound healing in diabetic rats.