title: In vivo biodegradation of porous silk fibroin films implanted beneath the skin and muscle of the rat.
abstract: Since the bioresorption process has a strong impact not only on the mechanical properties of the biomaterial but also on the extent of tissue regeneration, in vivo biodegradation of absorbable porous biomaterials plays a key role in tissue repair and wound healing. In the present work, porous silk fibroin films (PSFFs) were prepared by a freeze-drying method and then implanted beneath the dorsal skin and the femoral skeletal muscle of the rat. The objective was to study the rate of biodegradation of the PSFFs in different tissues, each with its distinct metabolic rate. In addition we examined the relationship between the biodegradation rate and tissue-regeneration rate semi-quantitatively by incorporating histology, microscopy and image analysis methods. Furthermore, based on our previous findings, we also explored the relationship between in vitro and in vivo rates of biodegradation. The results suggest that the PSFFs experience a similar biodegradation process regardless of the type of tissue in which they are implanted, in spite of the higher metabolic rate of the skeletal muscle. In addition, the in vitro biodegradation rate of the PSFFs was comparable to that of both skin and skeletal muscle, suggesting that an in vitro biodegradation test could be used to predict in vivo performance.
authors.affiliation: Key Laboratory of Textile Science & Technology of Ministry of Education, College of Textiles, Donghua University, 2999 North Renmin Road, Songjiang, Shanghai, China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Guan
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.forename: Mingzhong
authors.initials: M
authors.lastname: Li
authors.forename: Lun
authors.initials: L
authors.lastname: Bai
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D017364:Collagenases / Q000737:chemistry; D005349:Fibroins / Q000737:chemistry*; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000473:pathology; D016062:Porosity; D051381:Rats; D017207:Rats, Sprague-Dawley; D012038:Regeneration; D012867:Skin / Q000187:drug effects*; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds; D014945:Wound Healing
chemical_list: D001672:Biocompatible Materials; D005349:Fibroins; D017364:Collagenases
keywords: biodegradation; in vivo; porous biomaterials; silk fibroin