The objective of this study was to investigate the effect of gelatin(SG) isolated from salmon skin and its hydrolysate(SGH) on photoaging skin, and the mechanism responsible for anti-photoaging. The average molecular ...The objective of this study was to investigate the effect of gelatin(SG) isolated from salmon skin and its hydrolysate(SGH) on photoaging skin, and the mechanism responsible for anti-photoaging. The average molecular weights of SG and SGH were 65 k Da and 873 Da, respectively. The amino acid compositions of SG and SGH were similar. Both of them were abundant in hydrophobic amino acids. Twenty-five peptides were identified from SGH. SG and SGH could improve UV irradiation-induced pathological changes of macroscopical tissue texture and skin morphology. Hydroxyproline content is an indicator of matrix collagen content, SG and SGH could inhibit the decrease of hydroxyproline content in photoaging skin in a dose dependent manner. In addition, SG and SGH could alleviate UV irradiation-induced oxidative damages to skin by increasing the activities of total superoxide dismutase(T-SOD), glutathione peroxidase(GSH-Px) and catalase(CAT), increasing the content of glutathione(GSH) and decreasing the content of malonaldehyde(MDA). Moreover, SG and SGH could enhance immune regulation system by increasing the thymus index. Thus, the anti-photoaging mechanisms of SG and SGH were by inhibiting the depletion of antioxidant defense components, involving in the synthesis of collagen and enhancing the function of immune system. Besides, SGH showed a better result in protecting skin from photoaging than SG.展开更多
Hemostasis is a major challenge in surgical procedures and traumas. Conventional hemostatic methods have limited efficacy and may cause additional tissue damage. In this study, we designed a novel hemostatic agent bas...Hemostasis is a major challenge in surgical procedures and traumas. Conventional hemostatic methods have limited efficacy and may cause additional tissue damage. In this study, we designed a novel hemostatic agent based on the in situ gel formation of gelatin cross-linked by a novel microbial transglutaminase(mTGase), in which the amino acid sequences differed from commercial mTGases. The new hemostatic agent showed the same biochemical crosslinking chemistry as the final stages of the blood coagulation cascade while using gelatin as a "structural" protein(rather than fibrin) and a calcium-independent mTGase as the crosslinking catalyst(rather than factor XIIIa). In rat liver hemostasis models, the hemostatic agent not only showed a similar hemostatic effect as that of SURGIFLO~(positive control), but also stronger adhesion strength and elasticity than SURGIFLO~.Therefore, this biomimetic gelatin-mTGase mix hemostatic is a novel and effective surgical sealant.展开更多
基金supported by the National Natural Science Foundation of China (No.31401476)Specialized Research Fund for the Doctoral Program of Higher Education (No.20130132120024)+1 种基金the Fundamental Research Funds for The Central Universities (No.201313002)Shandong Province Regional Innovation and Development of Marine Economy Demonstration Projects
文摘The objective of this study was to investigate the effect of gelatin(SG) isolated from salmon skin and its hydrolysate(SGH) on photoaging skin, and the mechanism responsible for anti-photoaging. The average molecular weights of SG and SGH were 65 k Da and 873 Da, respectively. The amino acid compositions of SG and SGH were similar. Both of them were abundant in hydrophobic amino acids. Twenty-five peptides were identified from SGH. SG and SGH could improve UV irradiation-induced pathological changes of macroscopical tissue texture and skin morphology. Hydroxyproline content is an indicator of matrix collagen content, SG and SGH could inhibit the decrease of hydroxyproline content in photoaging skin in a dose dependent manner. In addition, SG and SGH could alleviate UV irradiation-induced oxidative damages to skin by increasing the activities of total superoxide dismutase(T-SOD), glutathione peroxidase(GSH-Px) and catalase(CAT), increasing the content of glutathione(GSH) and decreasing the content of malonaldehyde(MDA). Moreover, SG and SGH could enhance immune regulation system by increasing the thymus index. Thus, the anti-photoaging mechanisms of SG and SGH were by inhibiting the depletion of antioxidant defense components, involving in the synthesis of collagen and enhancing the function of immune system. Besides, SGH showed a better result in protecting skin from photoaging than SG.
基金supported by the National Basic Research Program of China (2015CB910400, 2012CB910400)National Natural Science Foundation of China (81472788, 81272463, 81330049)
文摘Hemostasis is a major challenge in surgical procedures and traumas. Conventional hemostatic methods have limited efficacy and may cause additional tissue damage. In this study, we designed a novel hemostatic agent based on the in situ gel formation of gelatin cross-linked by a novel microbial transglutaminase(mTGase), in which the amino acid sequences differed from commercial mTGases. The new hemostatic agent showed the same biochemical crosslinking chemistry as the final stages of the blood coagulation cascade while using gelatin as a "structural" protein(rather than fibrin) and a calcium-independent mTGase as the crosslinking catalyst(rather than factor XIIIa). In rat liver hemostasis models, the hemostatic agent not only showed a similar hemostatic effect as that of SURGIFLO~(positive control), but also stronger adhesion strength and elasticity than SURGIFLO~.Therefore, this biomimetic gelatin-mTGase mix hemostatic is a novel and effective surgical sealant.
