Study On Egg White Peptides Promoting Skin Wound Healing And Its Mechanism

Food-derived polypeptides are a certain kind of small molecular peptides which are generated from degradation of edible proteins using different methods,and final obtaining by further separation and purification.In recent years,food-derived peptides have attracted more and more attentions due to their properties,such as hypotensive,hypolipidemic and antibacterial.However,there are few studies on food-derived peptides in promoting skin cell migration and accelerating wound healing.Therefore,in this research,we studied the functions and mechanisms of egg white powder polypeptides on promoting skin cell migration and wound healing.In our previous work,we hydrolyzed egg white powder using a two-step enzyme hydrolysis method and separated the hydrolysate by ultrafiltration and sephadex column.We obtained four groups of peptides mixtures after separation and named them EWP1,EWP2,EWP3 and EWP4.In this study,we tested these four groups of peptides using transwell assay,respectively.Our data showed that EWP2 peptides remarkably promoted cell migration compared with other three groups.We further tested EWP2 peptides using a mouse skin wound model.Our results suggested that EWP2 accelerated mice skin wound healing compare with the control group.We then analyzed the constituents of EWP2 by LC-MS and identified 22 peptide sequences with high abundance in EWP2.We randomly chose 10 of these peptides to synthesize in two batches,respectively.Firstly,four peptides KPHAEVVLR ? KVEQGASVDKR ? ADQARELIN ?VNAIVFK were chosen to be synthesized to detect their functions on human skin fibroblast cells HSF.Transwell experiments results showed that KR-9 effectively promoted the migration of HSF cells.In addition,MTS experiments data demonstrated that KR-9 also promoted the proliferation of HSF cells.Next,we performed immunofluorescence and immunoblotting to explore the mechanism how KR-9 has this migration promoting activity.Our results indicated that KR-9 increased the protein level of membrane Hsp90?.Secondly,six peptides GASVDKR,DKEGKDVL,RVTEQESKPV,INFEKL,LYAEER,LRDILN were chosen to be sythesized.We used human keratinocytes Ha Ca T to detect whether these synthesized peptides could promote Ha Ca T cell migration.Our transwell,scratch wound healing and MTS assay results demonstrated that the peptide INFEKL could effectively promote the migration and proliferation of Ha Ca T.Immunoblotting results indicated that the mechanism of INFEKL promoting cell migration was to increase the protein levels of cytoplasmic and secreted Hsp90?.Next,we proved that INFEKL accelerated wound healing in the mice skin wound model.HE staining results indicated that INFEKL accelerated the process of epithelialization in the mice wound bed.In this study,we proved that egg white derived peptides could promote skin cells migration and accelerate mice wound healing by increasing extra-or intra-cellular Hsp90?.These finding indicated that food-derived peptides have great potential and application value in regulating cell migration,which provided new research ideas and theoretical proof for developing novel food-derived peptides to accelerate skin wound healing.