The present study aimed at making a rational usage for European eel bone by-products by preparing Europen eel bone peptide chelated calcium(EBPC-Ca).Nutritional properties and bioactivity of EBPC-Ca were evaluated.Res...The present study aimed at making a rational usage for European eel bone by-products by preparing Europen eel bone peptide chelated calcium(EBPC-Ca).Nutritional properties and bioactivity of EBPC-Ca were evaluated.Results showed that nutritional properties of calcium ions will cause intra-and inter-molecular folding and aggregation of peptide to uniformly form EBPC-Ca chelate.The chelated compound of EBPC and calcium ion triggered a strong apoptosis in heterogeneous human epithelial colorectal adenocarcinoma(Caco-2)in concentration-and time-dependent manners.Western blot analysis revealed that the EBPC-Ca induced apoptosis may be the result of a blocked autophagy flux through mitochondrial-dependent pathway.Additionally,the increase in FGF-23 protein expression inhibited the absorption of calcium ions and alleviated cell apoptosis.It was also found that the cell apoptosis occurs with significant increases in the levels of reactive oxygen species(ROS)and Ca^(2+)in the cells,indicating the anti-tumor potential of EBPC-Ca may involve multiple channels.展开更多
Calcium phosphate nanoparticles(CaPNPs)have good biocompatibility as gene carriers;however,CaPNPs typically exhibit a low transfection efficiency.Cell penetrate peptide(TAT)can increase the uptake of nanoparticles but...Calcium phosphate nanoparticles(CaPNPs)have good biocompatibility as gene carriers;however,CaPNPs typically exhibit a low transfection efficiency.Cell penetrate peptide(TAT)can increase the uptake of nanoparticles but is limited by its non-specificity.Grafting adhesion peptide adhesion peptide on carriers can enhance their targeting.The Plekho1 gene encodes casein kinase-2 interacting protein-1(CKIP-1),which can negatively regulate osteogenic differentiation.Based on the above,we produced a Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system via hydrothermal synthesis,silanization and adsorption.The effects of this carrier system on cell endocytosis and biological effects were evaluated by cell culture in vitro.The results demonstrate that CaPNPs with 7%Mg(60 nm particle size,short rod shape and good dispersion)were suitable for use as gene carriers.The carrier system boosted the endocytosis of MG63 cells and was helpful for promoting the differentiation of osteoblasts,and the dual-ligand system possessed a synergistic effect.The findings of this study show the tremendous potential of the Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system for efficient delivery into cells and osteogenesis inducement.展开更多
The calcium-binding activity of tilapia scale protein hydrolysates sequentially hydrolyzed by trypsin, flavor enzyme and pepsin were investigated. The hydrolysates were divided into four fractions using G-15 gel chrom...The calcium-binding activity of tilapia scale protein hydrolysates sequentially hydrolyzed by trypsin, flavor enzyme and pepsin were investigated. The hydrolysates were divided into four fractions using G-15 gel chromatography, and the F3 fraction has the higher calcium-binding activity of 196.3 mg/g. The UV-vis and the Fourier transform infrared spectroscopy (FTIR) demonstrate that the amino nitrogen atoms and the oxygen atoms belonging to the carboxylate groups are the primary binding sites for Ca2+. The X-ray diffraction and scanning electron microscopy (SEM) confirmed the reaction between the peptde and calcium. The results obtained indicated that this fish scale protein hydroly-sates have potential as functional foods for calcium-supplementation.展开更多
AIM To assess the direct effects of ischemia onintestinal epithelial integrity. Furthermore, clinicalefforts at mitigating the effect of hypoperfusion on gutpermeability have focused on restoring gut vascularfunction....AIM To assess the direct effects of ischemia onintestinal epithelial integrity. Furthermore, clinicalefforts at mitigating the effect of hypoperfusion on gutpermeability have focused on restoring gut vascularfunction.METHODS： we report that, in the Caco-2 cell modelof transepithelial transport, calcium glycerophosphate（CGP）, an inhibitor of intestinal alkaline phosphataseF3, has a significant effect to preserve transepithelialelectrical resistance （TEER） and to attenuate increasesin mannitol flux rates during hypoxia or cytokinestimulation.RESULTS： The effect was observable even at concentrationsas low as 1 μmol/L. As celiac disease is alsomarked by a loss of gut epithelial integrity, the effectof CGP to attenuate the effect of the α-gliadin peptide31-55 was also examined. In this instance, CGP exertedlittle effect of preservation of TEER, but significantlyattenuated peptide induced increase in mannitol flux.CONCLUSION： it appears that CGP treatment mightsynergize with other therapies to preserve gut epithelialintegrity.展开更多
Corticotropin-releasing factor(CRF), which activates the hypothalamic-pituitary-adrenal axis under stress, also has proinflammatory peripheral effects possibly through mast cells. The purpose of this study was to inve...Corticotropin-releasing factor(CRF), which activates the hypothalamic-pituitary-adrenal axis under stress, also has proinflammatory peripheral effects possibly through mast cells. The purpose of this study was to investigate the effect of urocortin (UCN), a 40-amino-acid CRF family peptide, on degranulation and intracellular calcium of rat lung mast cells. The activation and degranulation of mast cells were observed by Toluidine blue staining and transmission electron microscope. The intracellular calcium was investigated using confocal laser scanning microscopy and flow cytometry. The results indicated that all the three different concentrations of UCN(0.1, 1 and 10 mu M) significantly induced the activation and degranulation of rat lung mast cells in vitro. This effect was markedly blocked by selective CRF receptor 1(CRF-R1) antagonist antalarmin, but not by specific CRF receptor 2(CRF-R2) antagonist antisauvagine-30(anti-Svg-30). The results also showed that UCN caused a rapid peak increase inCa2+(i) at point of 300s after UCN treatment, followed by a decrease to a sustained plateau phase. The peak increase inCa2+(i) induced by UCN was significantly inhibited by antalarmin, but not by anti-Svg-30. This effect of UCN onCa2+(i) in rat lung mast cells was also found by flow cytometry. Regression analysis revealed a positive correlation between mast cells degranulation extent and the maximum value ofCa2+(i)(P < 0.01). Taken together, our present study suggested that UCN induced the increase of Ca2+(i) and degranulation of rat lung mast cells through CRF-R1. These findings may have implications for the pathophysiology of allergic and inflammatory lung disorders such as asthma, which is closely associated with mast cell activation and degranulation. Copyright (c) 2008 S. Karger AG, Basel.展开更多
基金supported by National Natural Science Foundation of China(NSFC,Grant No.31801459,Grant No.32072209)China Postdoctoral Science Foundation Funded Project(2020M682073)+1 种基金the Science and Technology General Projects of Fujian Province(2019J01393)Program of Innovative Research Team in Science and Technology in Fujian Province University([2020]12)。
文摘The present study aimed at making a rational usage for European eel bone by-products by preparing Europen eel bone peptide chelated calcium(EBPC-Ca).Nutritional properties and bioactivity of EBPC-Ca were evaluated.Results showed that nutritional properties of calcium ions will cause intra-and inter-molecular folding and aggregation of peptide to uniformly form EBPC-Ca chelate.The chelated compound of EBPC and calcium ion triggered a strong apoptosis in heterogeneous human epithelial colorectal adenocarcinoma(Caco-2)in concentration-and time-dependent manners.Western blot analysis revealed that the EBPC-Ca induced apoptosis may be the result of a blocked autophagy flux through mitochondrial-dependent pathway.Additionally,the increase in FGF-23 protein expression inhibited the absorption of calcium ions and alleviated cell apoptosis.It was also found that the cell apoptosis occurs with significant increases in the levels of reactive oxygen species(ROS)and Ca^(2+)in the cells,indicating the anti-tumor potential of EBPC-Ca may involve multiple channels.
基金Project(81571021)supported by the National Natural Science Foundation of ChinaProject(2018zzts944)supported by the Graduate Student Independent Exploration Innovation Fund of the Central South University,China+1 种基金Projects(2015WK3012,2018SK2017)supported by the Hunan Provincial Science and Technology Department,ChinaProject(20160301)supported by New Talent Project of the Third Xiangya Hospital of Central South University,China。
文摘Calcium phosphate nanoparticles(CaPNPs)have good biocompatibility as gene carriers;however,CaPNPs typically exhibit a low transfection efficiency.Cell penetrate peptide(TAT)can increase the uptake of nanoparticles but is limited by its non-specificity.Grafting adhesion peptide adhesion peptide on carriers can enhance their targeting.The Plekho1 gene encodes casein kinase-2 interacting protein-1(CKIP-1),which can negatively regulate osteogenic differentiation.Based on the above,we produced a Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system via hydrothermal synthesis,silanization and adsorption.The effects of this carrier system on cell endocytosis and biological effects were evaluated by cell culture in vitro.The results demonstrate that CaPNPs with 7%Mg(60 nm particle size,short rod shape and good dispersion)were suitable for use as gene carriers.The carrier system boosted the endocytosis of MG63 cells and was helpful for promoting the differentiation of osteoblasts,and the dual-ligand system possessed a synergistic effect.The findings of this study show the tremendous potential of the Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system for efficient delivery into cells and osteogenesis inducement.
文摘The calcium-binding activity of tilapia scale protein hydrolysates sequentially hydrolyzed by trypsin, flavor enzyme and pepsin were investigated. The hydrolysates were divided into four fractions using G-15 gel chromatography, and the F3 fraction has the higher calcium-binding activity of 196.3 mg/g. The UV-vis and the Fourier transform infrared spectroscopy (FTIR) demonstrate that the amino nitrogen atoms and the oxygen atoms belonging to the carboxylate groups are the primary binding sites for Ca2+. The X-ray diffraction and scanning electron microscopy (SEM) confirmed the reaction between the peptde and calcium. The results obtained indicated that this fish scale protein hydroly-sates have potential as functional foods for calcium-supplementation.
文摘AIM To assess the direct effects of ischemia onintestinal epithelial integrity. Furthermore, clinicalefforts at mitigating the effect of hypoperfusion on gutpermeability have focused on restoring gut vascularfunction.METHODS： we report that, in the Caco-2 cell modelof transepithelial transport, calcium glycerophosphate（CGP）, an inhibitor of intestinal alkaline phosphataseF3, has a significant effect to preserve transepithelialelectrical resistance （TEER） and to attenuate increasesin mannitol flux rates during hypoxia or cytokinestimulation.RESULTS： The effect was observable even at concentrationsas low as 1 μmol/L. As celiac disease is alsomarked by a loss of gut epithelial integrity, the effectof CGP to attenuate the effect of the α-gliadin peptide31-55 was also examined. In this instance, CGP exertedlittle effect of preservation of TEER, but significantlyattenuated peptide induced increase in mannitol flux.CONCLUSION： it appears that CGP treatment mightsynergize with other therapies to preserve gut epithelialintegrity.
文摘Corticotropin-releasing factor(CRF), which activates the hypothalamic-pituitary-adrenal axis under stress, also has proinflammatory peripheral effects possibly through mast cells. The purpose of this study was to investigate the effect of urocortin (UCN), a 40-amino-acid CRF family peptide, on degranulation and intracellular calcium of rat lung mast cells. The activation and degranulation of mast cells were observed by Toluidine blue staining and transmission electron microscope. The intracellular calcium was investigated using confocal laser scanning microscopy and flow cytometry. The results indicated that all the three different concentrations of UCN(0.1, 1 and 10 mu M) significantly induced the activation and degranulation of rat lung mast cells in vitro. This effect was markedly blocked by selective CRF receptor 1(CRF-R1) antagonist antalarmin, but not by specific CRF receptor 2(CRF-R2) antagonist antisauvagine-30(anti-Svg-30). The results also showed that UCN caused a rapid peak increase inCa2+(i) at point of 300s after UCN treatment, followed by a decrease to a sustained plateau phase. The peak increase inCa2+(i) induced by UCN was significantly inhibited by antalarmin, but not by anti-Svg-30. This effect of UCN onCa2+(i) in rat lung mast cells was also found by flow cytometry. Regression analysis revealed a positive correlation between mast cells degranulation extent and the maximum value ofCa2+(i)(P < 0.01). Taken together, our present study suggested that UCN induced the increase of Ca2+(i) and degranulation of rat lung mast cells through CRF-R1. These findings may have implications for the pathophysiology of allergic and inflammatory lung disorders such as asthma, which is closely associated with mast cell activation and degranulation. Copyright (c) 2008 S. Karger AG, Basel.
