title: Development of ethyl alcohol-precipitated silk sericin/polyvinyl alcohol scaffolds for accelerated healing of full-thickness wounds.
abstract: Silk sericin has been recently reported for its advantageous biological properties to promote wound healing. In this study, we established that the ethyl alcohol (EtOH) could be used to precipitate sericin and form the stable sericin/polyvinyl alcohol (PVA) scaffolds without the crosslinking. The sericin/PVA scaffolds were fabricated via freeze-drying and subsequently precipitating in various concentrations of EtOH. The EtOH-precipitated sericin/PVA scaffolds showed denser structure, higher compressive modulus, but lower water swelling ability than the non-precipitated scaffolds. Sericin could be released from the EtOH-precipitated sericin/PVA scaffolds in a sustained manner. After cultured with L929 mouse fibroblasts, the 70 vol% EtOH-precipitated sericin/PVA scaffolds showed the highest potential to promote cell proliferation. After applied to the full-thickness wounds of rats, the 70 vol% EtOH-precipitated sericin/PVA scaffolds showed significantly higher percentage of wound size reduction and higher extent of type III collagen formation and epithelialization, compared with the control scaffolds without sericin. The accelerated wound healing by the 70 vol% EtOH-precipitated sericin/PVA scaffolds was possibly due to (1) the bioactivity of sericin itself to promote wound healing, (2) the sustained release of precipitated sericin from the scaffolds, and (3) the activation and recruitment of wound healing-macrophages by sericin to the wounds. This finding suggested that the EtOH-precipitated sericin/PVA scaffolds were more effective for the wound healing, comparing with the EtOH-precipitated PVA scaffolds without sericin.
authors.affiliation: Bioactive Resources for Innovative Clinical Applications Research Unit, Chulalongkorn University and Department of Pharmacy Practice, Faculty of Pharmaceutical Sciences, Chulalongkorn University, PhayaThai Road, Phatumwan, Bangkok 10330, Thailand.
authors.forename: Tippawan
authors.initials: T
authors.lastname: Siritienthong
authors.forename: Juthamas
authors.initials: J
authors.lastname: Ratanavaraporn
authors.forename: Pornanong
authors.initials: P
authors.lastname: Aramwit
mesh_terms: D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D011232:Chemical Precipitation; D000431:Ethanol / Q000008:administration & dosage / Q000737:chemistry*; D008297:Male; D051379:Mice; D011142:Polyvinyl Alcohol / Q000008:administration & dosage / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D047030:Sericins / Q000008:administration & dosage / Q000737:chemistry*; D047011:Silk / Q000008:administration & dosage / Q000737:chemistry*; D012867:Skin / Q000187:drug effects / Q000293:injuries / Q000473:pathology; D054457:Tissue Scaffolds; D014945:Wound Healing / Q000187:drug effects
chemical_list: D047030:Sericins; D047011:Silk; D000431:Ethanol; D011142:Polyvinyl Alcohol