[ Objective ] This study aimed to extract antibacterial peptides from mussel. [ Method ] Blue mussels were used as raw materials for direct extraction of antibacterial peptides by using O. 5 % acetic acid, and the ant...[ Objective ] This study aimed to extract antibacterial peptides from mussel. [ Method ] Blue mussels were used as raw materials for direct extraction of antibacterial peptides by using O. 5 % acetic acid, and the antibacterial peptides were isolated and purified by Sephacryl S-100 polyacrylamide gel chromatography. The fractions were collected for measurement of antibacterial activity and minimum inhibitory concentration for a variety of bacterial species by filter paper diffusion assay. Molecular weight of the antibacterial peptides was determined by SDS-PAGE. Variation of antibacterial activity of antibacterial peptides was measured at 100 ~C under conditions of different processing time and different pH. [ Result] The O. 5% acetic acid was used for crude extraction of antibacterial peptides as extrac- tion solution and led to relatively high extraction efficiency. By using Sephacryl S-100, the antibacterial peptides could be purified as a single substance. The isola- ted and purified antibacterial peptides of mussel had relatively strong antibacterial properties with molecular weight of 5 908, showing heat-resistance acid-alkaline resistance. [ Conclusion] This study laid the theoretical foundation for large-scale production of antibacterial peotides.展开更多
P-113 is a fragment of natural occurring peptide Histatin 5 found in human saliva. This peptide exhibited broad spectrum of antibacterial and antifungal biological activities. In this study, bifunctional P-113 peptide...P-113 is a fragment of natural occurring peptide Histatin 5 found in human saliva. This peptide exhibited broad spectrum of antibacterial and antifungal biological activities. In this study, bifunctional P-113 peptides 2–5 were designed as Sortase A substrates and synthesized by solid support peptide synthesis,where the N-terminus were equipped with glycine and its analogues, and C-terminus were extended with LPETGGS, respectively. Under Sortase A catalyzed condition, head to tail cyclization products 7–10were afforded in yields from 76% to 93%. The conformation insights of linear peptides 2–5 and cyclic analogues 7–10 in aqueous buffers and in trifluroethanol（TFE） analyzed by circular dichroism（CD）suggested that a-helix structures were produced progressively in hydrophobic environment independent of the cyclization, which displayed the similar behavior as parent peptide P-113.展开更多
One antibacterial activity fraction from an immunized dipteran insect, Bactrocera dorsalis, was isolated and purified by prepurification, ion-exchange chromatography, gel filtration chromatography and reverse-phase hi...One antibacterial activity fraction from an immunized dipteran insect, Bactrocera dorsalis, was isolated and purified by prepurification, ion-exchange chromatography, gel filtration chromatography and reverse-phase high performance liquid chromatography （HPLC）. The final purified fraction was checked on the Smart system HPLC and was judged as a pure fraction. The results of physical and biological analysis revealed that this fraction is heat stable and showed strong activities against Gram-positive bacterial growth. It possesses antibicrobial peptide properties and is worth further investigation.展开更多
We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coliDH_(5α) to stimulate the antibacterial peptide followed by antibacterial activity assay,induction dynamic res...We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coliDH_(5α) to stimulate the antibacterial peptide followed by antibacterial activity assay,induction dynamic research and Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis(Tricine SDS-PAGE)experiment.The antibacterial activity of the induced BTI-Tn-5B1 cell line was the highest,and the antibacterial activity increased gradually to the highest level in 16 hours after stimulation.A new antibacterial peptide with a molecular weight of about 8000 Da was preferentially induced in Trichoplusia ni BTI-Tn-5B1 cells in 16 hours after stimulation.Antibacterial activity assays indicated that it had inhibition against Staphylococcus aureus,Escherichia coli K_(12)D_(31) and Salmonella derby.It has especially strong inhibition against Gram-negative bacteria such as Escherichia coli K_(12)D_(31) and Salmonella derby.展开更多
[ Objective ] The paper was to isolate and preliminarily identify the antibacterial active substances of antagonistic actinomyeete strain G19 obtained from the soil highly affected by peach crown gall （Agrobacterium ...[ Objective ] The paper was to isolate and preliminarily identify the antibacterial active substances of antagonistic actinomyeete strain G19 obtained from the soil highly affected by peach crown gall （Agrobacterium tumefaciens）. [ Method] The antibacterial substances of antagonistic actinomycete strain G19 were ex- tracted using protein precipitation method, then isolated and purified using high performance liquid chromatography and medium-pressure preparative chromatogra- phy. Its molecular weight was determined by MALDI-TOFMS method, and the related functional groups were verified through chemical color reaction. [ Result] Seven peptide portions were produced from the antibacterial substances of antagonistic actinomycete strain G19 with the molecular weights of 900 - 1 300 Da after isolation and purification. It could be also inferred that it contained Cys, and carried with H2O and Na＋. Color reaction of functional groups verified that the sub- stance was polypeptide containing glycosyl. [ Conclusion] The result provided basis for the final definition of the structure of antibacterial substances in antagonistic actinomycete strain G19.展开更多
The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformati...The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformation mediated by Agrobacterium tunefaciens EHA105, anti-bacterial peptide gene with strong bactericidal action to pathogenic bacteria was introduced into Chinese cabbage AB-81 self-bred line and the transgenic plants were obtained. PCR and Southern blotting detection showed that target gene was integrated into plant genome of Chinese cabbage. The tests of bacteriostasis action of the extract from transgenic plants in vitro, and the assay of disease-resistant of transgenic plantlets in the tube and the pot by perfusing inoculation with pathogenic bacteria showed obvious resistance to soft rot. This resistance can be a stable heredity by genetic analysis of generations of transgenic plants self-bred, separation ratio of its R, was 3:1. The resistance to Km and disease of soft rot was still kept in the R-5. These results indicated the possibility of breeding new varieties of anti-soft rot Chinese cabbage by transgenic plants as parents.展开更多
Antibacterial peptide is a small molecular weight,a substance existing in the biological body,plays a very important role in congenital immune systems.Today,in various antibiotics,the problem of drug resistance has ca...Antibacterial peptide is a small molecular weight,a substance existing in the biological body,plays a very important role in congenital immune systems.Today,in various antibiotics,the problem of drug resistance has caused people to live an indelible impact.Since the antibacterial peptide has spectral antibacterial properties,it has the characteristics of participating in human natural immunity and no residual,and is now one of the research and development hotspots.Antibacterial peptide is a recognized substance that can replace antibiotics,and people have never stopped,and new types of antimicrobial peptides have also emerged in the Volkswagen Vision.This paper is based on the use of antimicrosis peptides in daily life,briefly describes the effects of antimicrobial peptides in medical,animal husbandry and industrial.展开更多
In order to study the effects of Saussurea laniceps polysaccharides(SLPs)on the expression of inflammatory factors and antimicrobial peptide LL-37 in UVB-induced keratinocytes,SLPs were extracted by the ethanol therma...In order to study the effects of Saussurea laniceps polysaccharides(SLPs)on the expression of inflammatory factors and antimicrobial peptide LL-37 in UVB-induced keratinocytes,SLPs were extracted by the ethanol thermal reflux method,and SLPs at different concentrations were used to examine the inhibitory effect of COX-2(a key mediator of inflammatory pathway).A cell model of UVB irradiation-induced inflammation was established to determine the influence of SLPs on prostaglandin E2(PGE-2),TNF-αand IL-1βinflammatory factors,as well as the relationships of SLPs with LL-37 expression.An enzyme-linked immunosorbent assay(ELISA)and western blot analysis were used to detect the production of inflammatory factors and LL-37 antimicrobial peptide.The results showed that the inhibition rate of COX-2 was 82.41%at 1000μg/mL,and the expression of PGE-2,TNF-αand IL-1βinflammatory factors in HaCaT cells was significantly downregulated at 100μg/mL(P<0.01).In addition,SLPs at 50μg/mL and 100μg/mL concentrations enhanced the expression of LL-37 antimicrobial peptide(P<0.01),thereby down-regulating the expression of TNF-αand IL-1βinflammatory factors,then reducing skin inflammation.Conclusion:SLP can significantly inhibit the inflammatory response induced by UVB,and can further slow down the damage caused by inflammation to the skin by regulating LL-37 antimicrobial peptides,which has the potential to prevent skin inflammatory damage caused by UVB irradiation.展开更多
Metastatic dissemination is the major cause of death from breast-cancer(BC).Fusobacterium nucleatum(F.n)is widely enriched in BC and has recently been identified as one of the high-risk factors for promoting BC metast...Metastatic dissemination is the major cause of death from breast-cancer(BC).Fusobacterium nucleatum(F.n)is widely enriched in BC and has recently been identified as one of the high-risk factors for promoting BC metastasis.Here,with an experimental model,we demonstrated that intratumoral F.n induced BC aggressiveness by transcriptionally activating Epithelial-mesenchymal transition-associated genes.Therefore,the F.n may be a potential target to prevent metastasis.Given the fact that cancer-associated fibroblasts(CAFs)are abundant in BC and located near blood vessels,we report an optogenetic system that drives CAF to in situ produce human antibacterial peptide LL37,with the characteristics of biosafety and freely intercellular trafficking,for depleting intratumoral F.n,leading to a 72.1%reduction in lung metastatic nodules number without affecting the balance of the systemic flora.Notably,mild photothermal treatment was found that could normalize CAF,contributing to synergistically inhibiting BC metastasis.In addition,the system can also simultaneously encode a gene of TNF-related apoptosis-inducing ligand to suppress the primary tumor.Together,our study highlights the potential of local elimination of tumor pathogenic bacteria to prevent BC metastasis.展开更多
The repair of tissue injuries,particularly irregular bone defects,continues to pose a significant challenge in the surgical field.Long-term enhancements in mechanical support,inflammation control,and osteogenic activi...The repair of tissue injuries,particularly irregular bone defects,continues to pose a significant challenge in the surgical field.Long-term enhancements in mechanical support,inflammation control,and osteogenic activity are essential for effective treatment of bone defects.Despite the development of numerous scaffold materials for bone regeneration,their limitations in shape adaptability,tissue adhesion,and immunomodulatory capabilities have restricted their applications in repairing irregular bone defects.Herein,we introduce a supramolecular assembly strategy for fabricating scaffolds based on polyphenols,polypeptides,and clay nanosheets(CNSs).This method synergistically integrates robust bio-adhesion,superior mechanical properties,and immunoregulatory functionality into a self-healing hydrogel system designed for treating irregular bone defects.The catechol and guanidinium groups within the hydrogel enable strong adhesion to bone tissue while exhibiting excellent antimicrobial and immunomodulatory activities.Furthermore,the incorporation of CNSs not only enhances the mechanical strength of the hydrogels but also significantly promotes the osteogenic differentiation of bone mesenchymal stem cells through the release of bioactive ions.In vivo studies demonstrated that the mechanically nano-enhanced,bio-adhesive,and immunomodulatory hydrogel effectively adapts to defects,adheres to bone tissue,positively regulates the inflammatory microenvironment,and ultimately accelerates the healing of bone defects,representing a promising and versatile strategy for the regeneration of bone and other tissue injuries.展开更多
The repair of infective bone defects is a great challenge in clinical work.It is of vital importance to develop a kind of bone scaffold with good osteogenic properties and long-term antibacterial activity for local an...The repair of infective bone defects is a great challenge in clinical work.It is of vital importance to develop a kind of bone scaffold with good osteogenic properties and long-term antibacterial activity for local anti-infection and bone regeneration.A porous mineralized collagen(MC)scaffold containing poly(D,L-lactide-co-glycolic acid)(PLGA)microspheres loaded with two antibacterial synthetic peptides,Pac-525 or KSL-W was developed and characterized via scanning electron microscopy(SEM),porosity measurement,swelling and mechanical tests.The results showed that the MC scaffold embedded with smooth and compact PLGA microspheres had a positive effect on cell growth and also had antibacterial properties.Through toxicity analysis,cell morphology and proliferation analysis and alkaline phosphatase evaluation,the antibacterial scaffolds showed excellent biocompatibility and osteogenic activity.The antibacterial property evaluated with Staphylococcus aureus and Escherichia coli suggested that the sustained release of Pac-525 or KSL-W from the scaffolds could inhibit the bacterial growth aforementioned in the long term.Our results suggest that the antimicrobial peptides-loaded MC bone scaffold has good antibacterial and osteogenic activities,thus providing a great promise for the treatment of infective bone defects.展开更多
Thrombosis and infection are pivotal clinical complications associated with interventional blood-contacting devices,leading to significant morbidity and mortality.To address these issues,we present a stepwise metal-ca...Thrombosis and infection are pivotal clinical complications associated with interventional blood-contacting devices,leading to significant morbidity and mortality.To address these issues,we present a stepwise metal-catechol-(amine)(MCA)surface engineering strategy that efficiently integrates therapeutic nitric oxide(NO)gas and antibacterial peptide(ABP)onto catheters,ensuring balanced anti-thrombotic and anti-infective properties.First,copper ions were controllably incorporated with norepinephrine and hexanediamine through a one-step molecular/ion co-assembly process,creating a NO-generating and amine-rich MCA surface coating.Subsequently,azide-polyethylene glycol 4-N-hydroxysuccinimidyl and dibenzylcyclooctyne modified ABP were sequentially immobilized on the surface via amide coupling and bioorthogonal click chemistry,ensuring the dense grafting of ABP while maintaining the catalytic efficacy for NO.This efficient integration of ABP and NO-generating ability on the catheter surface provides potent antibacterial properties and ability to resist adhesion and activation of platelets,thus synergistically preventing infection and thrombosis.We anticipate that this synergistic modification strategy will offer an effective solution for advancing surface engineering and enhancing the clinical performance of biomedical devices.展开更多
基金Supported by Natural Science Foundation of Shandong Province ( ZR2009BM0190A)
文摘[ Objective ] This study aimed to extract antibacterial peptides from mussel. [ Method ] Blue mussels were used as raw materials for direct extraction of antibacterial peptides by using O. 5 % acetic acid, and the antibacterial peptides were isolated and purified by Sephacryl S-100 polyacrylamide gel chromatography. The fractions were collected for measurement of antibacterial activity and minimum inhibitory concentration for a variety of bacterial species by filter paper diffusion assay. Molecular weight of the antibacterial peptides was determined by SDS-PAGE. Variation of antibacterial activity of antibacterial peptides was measured at 100 ~C under conditions of different processing time and different pH. [ Result] The O. 5% acetic acid was used for crude extraction of antibacterial peptides as extrac- tion solution and led to relatively high extraction efficiency. By using Sephacryl S-100, the antibacterial peptides could be purified as a single substance. The isola- ted and purified antibacterial peptides of mussel had relatively strong antibacterial properties with molecular weight of 5 908, showing heat-resistance acid-alkaline resistance. [ Conclusion] This study laid the theoretical foundation for large-scale production of antibacterial peotides.
基金supported by the National Natural Science Foundation of China(No.21472070)the Project for Jiangsu Scientific and Technological Innovation Team+2 种基金Fund for Jiangsu Distinguished Professorship ProgramProject Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,the 111 Project(No.111-2-06)the Jiangsu province“Collaborative Innovation Center for Advanced Industrial Fermentation”industry development program
文摘P-113 is a fragment of natural occurring peptide Histatin 5 found in human saliva. This peptide exhibited broad spectrum of antibacterial and antifungal biological activities. In this study, bifunctional P-113 peptides 2–5 were designed as Sortase A substrates and synthesized by solid support peptide synthesis,where the N-terminus were equipped with glycine and its analogues, and C-terminus were extended with LPETGGS, respectively. Under Sortase A catalyzed condition, head to tail cyclization products 7–10were afforded in yields from 76% to 93%. The conformation insights of linear peptides 2–5 and cyclic analogues 7–10 in aqueous buffers and in trifluroethanol（TFE） analyzed by circular dichroism（CD）suggested that a-helix structures were produced progressively in hydrophobic environment independent of the cyclization, which displayed the similar behavior as parent peptide P-113.
基金Acknowledgments We thank Prof. X.-F. Pang, late Academician of Chinese Academy of Science, for his support in getting this project started. We also thank Prof. Yamakawa （National of Institute of Sericultural and Entomological Science, Japan） for analyzing the purity of the final purified fraction. We thank Dr H. Ma for his suggestions on this project and reading our manuscript. This work was supported partly by the Natural Science Foundation of Guangdong Province （032256）, the National Basic Research Program of China under grant 2005CB121000 and the National Natural Science Foundation （30370716）.
文摘One antibacterial activity fraction from an immunized dipteran insect, Bactrocera dorsalis, was isolated and purified by prepurification, ion-exchange chromatography, gel filtration chromatography and reverse-phase high performance liquid chromatography （HPLC）. The final purified fraction was checked on the Smart system HPLC and was judged as a pure fraction. The results of physical and biological analysis revealed that this fraction is heat stable and showed strong activities against Gram-positive bacterial growth. It possesses antibicrobial peptide properties and is worth further investigation.
基金supported by grants from the National Basic Research Program of China (No.2002CCA02400)the Natural Science Foundation of China (Grant No.20475019)Qimingxing Project of Shanghai in China.
文摘We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coliDH_(5α) to stimulate the antibacterial peptide followed by antibacterial activity assay,induction dynamic research and Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis(Tricine SDS-PAGE)experiment.The antibacterial activity of the induced BTI-Tn-5B1 cell line was the highest,and the antibacterial activity increased gradually to the highest level in 16 hours after stimulation.A new antibacterial peptide with a molecular weight of about 8000 Da was preferentially induced in Trichoplusia ni BTI-Tn-5B1 cells in 16 hours after stimulation.Antibacterial activity assays indicated that it had inhibition against Staphylococcus aureus,Escherichia coli K_(12)D_(31) and Salmonella derby.It has especially strong inhibition against Gram-negative bacteria such as Escherichia coli K_(12)D_(31) and Salmonella derby.
基金Supported by Beijing Natural Science Foundation( 5112010)Beijing Municipal Education Commission Grant ( KM200910020001)~~
文摘[ Objective ] The paper was to isolate and preliminarily identify the antibacterial active substances of antagonistic actinomyeete strain G19 obtained from the soil highly affected by peach crown gall （Agrobacterium tumefaciens）. [ Method] The antibacterial substances of antagonistic actinomycete strain G19 were ex- tracted using protein precipitation method, then isolated and purified using high performance liquid chromatography and medium-pressure preparative chromatogra- phy. Its molecular weight was determined by MALDI-TOFMS method, and the related functional groups were verified through chemical color reaction. [ Result] Seven peptide portions were produced from the antibacterial substances of antagonistic actinomycete strain G19 with the molecular weights of 900 - 1 300 Da after isolation and purification. It could be also inferred that it contained Cys, and carried with H2O and Na＋. Color reaction of functional groups verified that the sub- stance was polypeptide containing glycosyl. [ Conclusion] The result provided basis for the final definition of the structure of antibacterial substances in antagonistic actinomycete strain G19.
文摘The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformation mediated by Agrobacterium tunefaciens EHA105, anti-bacterial peptide gene with strong bactericidal action to pathogenic bacteria was introduced into Chinese cabbage AB-81 self-bred line and the transgenic plants were obtained. PCR and Southern blotting detection showed that target gene was integrated into plant genome of Chinese cabbage. The tests of bacteriostasis action of the extract from transgenic plants in vitro, and the assay of disease-resistant of transgenic plantlets in the tube and the pot by perfusing inoculation with pathogenic bacteria showed obvious resistance to soft rot. This resistance can be a stable heredity by genetic analysis of generations of transgenic plants self-bred, separation ratio of its R, was 3:1. The resistance to Km and disease of soft rot was still kept in the R-5. These results indicated the possibility of breeding new varieties of anti-soft rot Chinese cabbage by transgenic plants as parents.
基金support provided by the National Natural Science Foundation of China(No.31900861).
文摘Antibacterial peptide is a small molecular weight,a substance existing in the biological body,plays a very important role in congenital immune systems.Today,in various antibiotics,the problem of drug resistance has caused people to live an indelible impact.Since the antibacterial peptide has spectral antibacterial properties,it has the characteristics of participating in human natural immunity and no residual,and is now one of the research and development hotspots.Antibacterial peptide is a recognized substance that can replace antibiotics,and people have never stopped,and new types of antimicrobial peptides have also emerged in the Volkswagen Vision.This paper is based on the use of antimicrosis peptides in daily life,briefly describes the effects of antimicrobial peptides in medical,animal husbandry and industrial.
文摘In order to study the effects of Saussurea laniceps polysaccharides(SLPs)on the expression of inflammatory factors and antimicrobial peptide LL-37 in UVB-induced keratinocytes,SLPs were extracted by the ethanol thermal reflux method,and SLPs at different concentrations were used to examine the inhibitory effect of COX-2(a key mediator of inflammatory pathway).A cell model of UVB irradiation-induced inflammation was established to determine the influence of SLPs on prostaglandin E2(PGE-2),TNF-αand IL-1βinflammatory factors,as well as the relationships of SLPs with LL-37 expression.An enzyme-linked immunosorbent assay(ELISA)and western blot analysis were used to detect the production of inflammatory factors and LL-37 antimicrobial peptide.The results showed that the inhibition rate of COX-2 was 82.41%at 1000μg/mL,and the expression of PGE-2,TNF-αand IL-1βinflammatory factors in HaCaT cells was significantly downregulated at 100μg/mL(P<0.01).In addition,SLPs at 50μg/mL and 100μg/mL concentrations enhanced the expression of LL-37 antimicrobial peptide(P<0.01),thereby down-regulating the expression of TNF-αand IL-1βinflammatory factors,then reducing skin inflammation.Conclusion:SLP can significantly inhibit the inflammatory response induced by UVB,and can further slow down the damage caused by inflammation to the skin by regulating LL-37 antimicrobial peptides,which has the potential to prevent skin inflammatory damage caused by UVB irradiation.
基金supported by the National Natural Science Foundation of China(82172762,21904119,and 82073395)Science and technology innovation talents support project of Henan Province(23HASTIT041)Henan Science Fund for Outstanding Young Scholars(232300421051,China).
文摘Metastatic dissemination is the major cause of death from breast-cancer(BC).Fusobacterium nucleatum(F.n)is widely enriched in BC and has recently been identified as one of the high-risk factors for promoting BC metastasis.Here,with an experimental model,we demonstrated that intratumoral F.n induced BC aggressiveness by transcriptionally activating Epithelial-mesenchymal transition-associated genes.Therefore,the F.n may be a potential target to prevent metastasis.Given the fact that cancer-associated fibroblasts(CAFs)are abundant in BC and located near blood vessels,we report an optogenetic system that drives CAF to in situ produce human antibacterial peptide LL37,with the characteristics of biosafety and freely intercellular trafficking,for depleting intratumoral F.n,leading to a 72.1%reduction in lung metastatic nodules number without affecting the balance of the systemic flora.Notably,mild photothermal treatment was found that could normalize CAF,contributing to synergistically inhibiting BC metastasis.In addition,the system can also simultaneously encode a gene of TNF-related apoptosis-inducing ligand to suppress the primary tumor.Together,our study highlights the potential of local elimination of tumor pathogenic bacteria to prevent BC metastasis.
基金the Ethics Com-mittee of Soochow University(No.SUDA20250122A03)animal experiments were conducted in accordance with the Regulations for the Management of Animal Experiments of the Animal Experimentation Management Committee of Soochow University.
文摘The repair of tissue injuries,particularly irregular bone defects,continues to pose a significant challenge in the surgical field.Long-term enhancements in mechanical support,inflammation control,and osteogenic activity are essential for effective treatment of bone defects.Despite the development of numerous scaffold materials for bone regeneration,their limitations in shape adaptability,tissue adhesion,and immunomodulatory capabilities have restricted their applications in repairing irregular bone defects.Herein,we introduce a supramolecular assembly strategy for fabricating scaffolds based on polyphenols,polypeptides,and clay nanosheets(CNSs).This method synergistically integrates robust bio-adhesion,superior mechanical properties,and immunoregulatory functionality into a self-healing hydrogel system designed for treating irregular bone defects.The catechol and guanidinium groups within the hydrogel enable strong adhesion to bone tissue while exhibiting excellent antimicrobial and immunomodulatory activities.Furthermore,the incorporation of CNSs not only enhances the mechanical strength of the hydrogels but also significantly promotes the osteogenic differentiation of bone mesenchymal stem cells through the release of bioactive ions.In vivo studies demonstrated that the mechanically nano-enhanced,bio-adhesive,and immunomodulatory hydrogel effectively adapts to defects,adheres to bone tissue,positively regulates the inflammatory microenvironment,and ultimately accelerates the healing of bone defects,representing a promising and versatile strategy for the regeneration of bone and other tissue injuries.
基金sponsored by the National Natural Science Foundation of China(Grant Nos 31771056,81671827,51572144,61571077,61871068)the National Key R&D Program of China(No.2018YFB0704304).
文摘The repair of infective bone defects is a great challenge in clinical work.It is of vital importance to develop a kind of bone scaffold with good osteogenic properties and long-term antibacterial activity for local anti-infection and bone regeneration.A porous mineralized collagen(MC)scaffold containing poly(D,L-lactide-co-glycolic acid)(PLGA)microspheres loaded with two antibacterial synthetic peptides,Pac-525 or KSL-W was developed and characterized via scanning electron microscopy(SEM),porosity measurement,swelling and mechanical tests.The results showed that the MC scaffold embedded with smooth and compact PLGA microspheres had a positive effect on cell growth and also had antibacterial properties.Through toxicity analysis,cell morphology and proliferation analysis and alkaline phosphatase evaluation,the antibacterial scaffolds showed excellent biocompatibility and osteogenic activity.The antibacterial property evaluated with Staphylococcus aureus and Escherichia coli suggested that the sustained release of Pac-525 or KSL-W from the scaffolds could inhibit the bacterial growth aforementioned in the long term.Our results suggest that the antimicrobial peptides-loaded MC bone scaffold has good antibacterial and osteogenic activities,thus providing a great promise for the treatment of infective bone defects.
基金supported by the National Natural Science Foundation of China(Project 82072072,32261160372,32171326,32371377)the Guang Dong Basic and Applied Basic Research Foundation(2022B1515130010)+1 种基金the Natural Science Foundation of Guangdong Province(2022A1515011442)Dongguan Science and Technology of Social Development Program(20231800906311,20221800906322).
文摘Thrombosis and infection are pivotal clinical complications associated with interventional blood-contacting devices,leading to significant morbidity and mortality.To address these issues,we present a stepwise metal-catechol-(amine)(MCA)surface engineering strategy that efficiently integrates therapeutic nitric oxide(NO)gas and antibacterial peptide(ABP)onto catheters,ensuring balanced anti-thrombotic and anti-infective properties.First,copper ions were controllably incorporated with norepinephrine and hexanediamine through a one-step molecular/ion co-assembly process,creating a NO-generating and amine-rich MCA surface coating.Subsequently,azide-polyethylene glycol 4-N-hydroxysuccinimidyl and dibenzylcyclooctyne modified ABP were sequentially immobilized on the surface via amide coupling and bioorthogonal click chemistry,ensuring the dense grafting of ABP while maintaining the catalytic efficacy for NO.This efficient integration of ABP and NO-generating ability on the catheter surface provides potent antibacterial properties and ability to resist adhesion and activation of platelets,thus synergistically preventing infection and thrombosis.We anticipate that this synergistic modification strategy will offer an effective solution for advancing surface engineering and enhancing the clinical performance of biomedical devices.
