Proteomic Analysis of Silk Fibroin Reveals Diverse Biological Function of Different Degumming Processing From Different Origin.

Yaling Wang,Jiacen Huang,Yunyun Liang,Xuejun Ni,Zhixin Xu,Yisheng Gao,Yumin Yang,Yahong Zhao,Xiaoming Yang

doi:10.3389/fbioe.2021.777320

Abstract

Silk, as a kind of natural fibrin, has been prepared into various biomaterials due to its excellent biocompatibility and mechanicalness. However, there are some controversies on the biocompatibility of silk fibroin (SF), especially when it coexists with sericin. In this study, two kinds of silk from Jiangsu and Zhejiang were degummed with two concentrations of Na2CO3 solution, respectively, to obtain four kinds of silk fibroin. The effects of different degumming treatments on silk fibroin properties were analyzed by means of color reaction, apparent viscosity measurement, and transmission electron microscope and isobaric tags for relative and absolute quantification analyses, and the effects of different silk fibroin membranes on the growth of Schwann cells were evaluated. The results showed that the natural silk from Zhejiang treated with 0.05% Na2CO3 solution had a fuller structure, higher apparent viscosity, and better protein composition. While SF obtained by degumming with 0.5% Na2CO3 solution was more beneficial to cell adhesion and proliferation due to the thorough removal of sericin. This study may provide important theoretical and experimental bases for the selection of biomaterials for fabricating artificial nerve grafts.

Highlights

Peripheral nerve repair has been one of the difficult problems in the field of neuroscience, especially the repair of long-distance serious injury
The degumming degree of two kinds of Na2CO3 solutions on the raw silk from different sources was determined by the picric acid–carmine staining method
Silk fibroin turns yellow in alkaline solution due to its selective adsorption of picric acid

Summary

Introduction

Peripheral nerve repair has been one of the difficult problems in the field of neuroscience, especially the repair of long-distance serious injury. In the past few decades, a large number of natural or synthetic materials, such as chitosan (Wang et al, 2005; Demina et al, 2017; Yu et al, 2017), silk fibroin (Baecker et al, 2017; Luo and Shao, 2017), collagen (Sayanagi et al, 2020), and poly (lactic-co-glycolic acid) (Wang et al, 2014), have been used to prepare artificial nerve grafts. Silk is a kind of natural high-molecular-protein polymer, which is synthesized in the special glands of the epithelial cells of silkworms, secreted into the cavity, and spun into fibers. It mainly contains silk fibroin (SF) and sericin. The content of SF accounts for most of the silk, about 70–80%, and sericin accounts for about 20–30%

Results

Discussion

Conclusion