The repair and motor functional recovery after spinal cord injury(SCI)remains a worldwide challenge.The inflammatory microenvironment is one of main obstacles on inhibiting the recovery of SCI.Using mesenchymal stem c...The repair and motor functional recovery after spinal cord injury(SCI)remains a worldwide challenge.The inflammatory microenvironment is one of main obstacles on inhibiting the recovery of SCI.Using mesenchymal stem cells(MSCs)derived extracellular vesicles to replace MSCs transplantation and mimic cell paracrine secretions provides a potential strategy for microenvironment regulation.However,the effective preservation and controlled release of extracellular vesicles in the injured spinal cord tissue are still not satisfied.Herein,we fabricated an injectable adhesive anti-inflammatory F127-polycitrate-polyethyleneimine hydrogel(FE)with sustainable and long term extracellular vesicle release(FE@EVs)for improving motor functional recovery after SCI.The orthotopic injection of FE@EVs hydrogel could encapsulate extracellular vesicles on the injured spinal cord,thereby synergistically induce efficient integrated regulation through suppressing fibrotic scar formation,reducing inflammatory reaction,promoting remyelination and axonal regeneration.This study showed that combining extracellular vesicles into bioactive multifunctional hydrogel should have great potential in achieving satisfactory locomotor recovery of central nervous system diseases.展开更多
Circular RNAs(circRNAs)play a critical regulatory role in degenerative diseases;however,their functions and therapeutic applications in intervertebral disc degeneration(IVDD)have not been explored.Here,we identified t...Circular RNAs(circRNAs)play a critical regulatory role in degenerative diseases;however,their functions and therapeutic applications in intervertebral disc degeneration(IVDD)have not been explored.Here,we identified that a novel circATXN1 highly accumulates in aging nucleus pulposus cells(NPCs)accountable for IVDD.CircATXN1 accelerates cellular senescence,disrupts extracellular matrix organization,and inhibits mitochondrial respiration.Mechanistically,circATXN1,regulated by heterogeneous nuclear ribonucleoprotein A2B1-mediated splicing circularization,promotes progerin translocation from the cell nucleus to the cytoplasm and inhibits the expression of insulin-like growth factor 1 receptor(IGF-1R).To demonstrate the therapeutic potential of circATXN1,siRNA targeting the backsplice junction of circATNX1 was screened and delivered by tetrahedral framework nucleic acids(tFNAs)due to their unique compositional and tetrahedral structural features.Our siRNA delivery system demonstrates superior abilities to transfect aging cells,clear intracellular ROS,and enhanced biological safety.Using siRNA–tFNAs to silence circATXN1,aging NPCs exhibit reduced mislocalization of progerin in the cytoplasm and up-regulation of IGF-1R,thereby demonstrating a rejuvenated cellular phenotype and improved mitochondrial function.In vivo,administering an aging cell-adapted siRNA nucleic acid framework delivery system to progerin pathologically expressed premature aging mice(zmpste24^(−/−))can ameliorate the cellular matrix in the nucleus pulposus tissue,effectively delaying IVDD.This study not only identified circATXN1 functioning as a cell senescence promoter in IVDD for the first time,but also successfully demonstrated its therapeutic potential via a tFNA-based siRNA delivery strategy.展开更多
The current effective method for treatment of spinal cord injury(SCI)is to reconstruct the biological microenvironment by filling the injured cavity area and increasing neuronal differentiation of neural stem cells(NS...The current effective method for treatment of spinal cord injury(SCI)is to reconstruct the biological microenvironment by filling the injured cavity area and increasing neuronal differentiation of neural stem cells(NSCs)to repair SCI.However,the method is characterized by several challenges including irregular wounds,and mechanical and electrical mismatch of the material-tissue interface.In the current study,a unique and facile agarose/gelatin/polypyrrole(Aga/Gel/PPy,AGP3)hydrogel with similar conductivity and modulus as the spinal cord was developed by altering the concentration of Aga and PPy.The gelation occurred through non-covalent interactions,and the physically crosslinked features made the AGP3 hydrogels injectable.In vitro cultures showed that AGP3 hydrogel exhibited excellent biocompatibility,and promoted differentiation of NSCs toward neurons whereas it inhibited over-proliferation of astrocytes.The in vivo implanted AGP3 hydrogel completely covered the tissue defects and reduced injured cavity areas.In vivo studies further showed that the AGP3 hydrogel provided a biocompatible microenvironment for promoting endogenous neurogenesis rather than glial fibrosis formation,resulting in significant functional recovery.RNA sequencing analysis further indicated that AGP3 hydrogel significantly modulated expression of neurogenesis-related genes through intracellular Ca2+signaling cascades.Overall,this supramolecular strategy produces AGP3 hydrogel that can be used as favorable biomaterials for SCI repair by filling the cavity and imitating the physiological properties of the spinal cord.展开更多
Cell transplantation has been proved the promising therapeutic effects on intervertebral disc degeneration(IVDD).However,the increased levels of reactive oxygen species(ROS)in the degenerated region will impede the ef...Cell transplantation has been proved the promising therapeutic effects on intervertebral disc degeneration(IVDD).However,the increased levels of reactive oxygen species(ROS)in the degenerated region will impede the efficiency of human adipose-derived stem cells(human ADSCs)transplantation therapy.It inhibits human ADSCs proliferation,and increases human ADSCs apoptosis.Herein,we firstly devised a novel amphiphilic copolymer PEG-PAPO,which could self-assemble into a nanosized micelle and load lipophilic kartogenin(KGN),as a single complex(PAKM).It was an injectable esterase-responsive micelle,and showed controlled release ability of KGN and apocynin(APO).Oxidative stimulation promoted the esterase activity in human ADSCs,which accelerate degradation of esterase-responsive micelle.Compared its monomer,the PAKM micelle possessed better bioactivities,which were attributed to their synergistic effect.It enhanced the viability,autophagic activation(P62,LC3 II),ECM-related transcription factor(SOX9),and ECM(Collagen II,Aggrecan)maintenance in human ADSCs.Furthermore,it is demonstrated that the injection of PAKM with human ADSCs yielded higher disc height and water content in rats.Therefore,PAKM micelles perform promoting cell survival and differentiation effects,and may be a potential therapeutic agent for IVDD.展开更多
Human influenza viruses preferentially bind to sialic acid-α2,6-galactose (SAα2,6Gal) receptors, which are predominant in human upper respiratory epithelia, whereas avian influenza viruses preferentially bind to SA...Human influenza viruses preferentially bind to sialic acid-α2,6-galactose (SAα2,6Gal) receptors, which are predominant in human upper respiratory epithelia, whereas avian influenza viruses preferentially bind to SAα2,3Gal receptors. However, variants with amino acid substitutions around the receptor-binding sites of the hemagglutinin (HA) protein can be selected after several passages of human influenza viruses from patients’ respiratory samples in the allantoic cavities of embryonated chicken eggs. In this study, we detected an egg-adapted HA S190R mutation in the pandemic H1N1 virus 2009 (pdmH1N1), and evaluated the effects of this mutation on receptor binding affinity and pathogenicity in mice. Our results revealed that residue 190 is located within the pocket structure of the receptor binding site. The single mutation to arginine at position 190 slightly increased the binding affinity of the virus to the avian receptor and decreased its binding to the long human α2,6-linked sialic acid receptor. Our study demonstrated that the S190R mutation resulted in earlier death and higher weight loss in mice compared with the wild-type virus. Higher viral titers at 1 dpi (days post infection) and diffuse damage at 4 dpi were observed in the lung tissues of mice infected with the mutant virus.展开更多
基金supported by National Natural Science Foundation of China(Grant No.51872224,81772379,81972096 and 81902238)Zhejiang Province Health Foundation,China(Grant No.2018KY092,WKJ-ZJ-1903)Nature Science Foundation of Zhejiang Province,China(Grant No.LQ18H060003).
文摘The repair and motor functional recovery after spinal cord injury(SCI)remains a worldwide challenge.The inflammatory microenvironment is one of main obstacles on inhibiting the recovery of SCI.Using mesenchymal stem cells(MSCs)derived extracellular vesicles to replace MSCs transplantation and mimic cell paracrine secretions provides a potential strategy for microenvironment regulation.However,the effective preservation and controlled release of extracellular vesicles in the injured spinal cord tissue are still not satisfied.Herein,we fabricated an injectable adhesive anti-inflammatory F127-polycitrate-polyethyleneimine hydrogel(FE)with sustainable and long term extracellular vesicle release(FE@EVs)for improving motor functional recovery after SCI.The orthotopic injection of FE@EVs hydrogel could encapsulate extracellular vesicles on the injured spinal cord,thereby synergistically induce efficient integrated regulation through suppressing fibrotic scar formation,reducing inflammatory reaction,promoting remyelination and axonal regeneration.This study showed that combining extracellular vesicles into bioactive multifunctional hydrogel should have great potential in achieving satisfactory locomotor recovery of central nervous system diseases.
基金supported by the Distinguished Young Scientist Fund of Zhejiang Province(LR23H060001)National Natural Science Foundation of China(Nos.82272480,82372486,82072481,21975217,and 82072465)+1 种基金“Pioneer”and“Leading Goose”R&D Program of Zhejiang(2024C03243)Dynamic Research Enterprise for Multidisciplinary Engineering Sciences(DREMES)at Zhejiang University and the University of Illinois at Urbana-Champaign,funded by Zhejiang University.
文摘Circular RNAs(circRNAs)play a critical regulatory role in degenerative diseases;however,their functions and therapeutic applications in intervertebral disc degeneration(IVDD)have not been explored.Here,we identified that a novel circATXN1 highly accumulates in aging nucleus pulposus cells(NPCs)accountable for IVDD.CircATXN1 accelerates cellular senescence,disrupts extracellular matrix organization,and inhibits mitochondrial respiration.Mechanistically,circATXN1,regulated by heterogeneous nuclear ribonucleoprotein A2B1-mediated splicing circularization,promotes progerin translocation from the cell nucleus to the cytoplasm and inhibits the expression of insulin-like growth factor 1 receptor(IGF-1R).To demonstrate the therapeutic potential of circATXN1,siRNA targeting the backsplice junction of circATNX1 was screened and delivered by tetrahedral framework nucleic acids(tFNAs)due to their unique compositional and tetrahedral structural features.Our siRNA delivery system demonstrates superior abilities to transfect aging cells,clear intracellular ROS,and enhanced biological safety.Using siRNA–tFNAs to silence circATXN1,aging NPCs exhibit reduced mislocalization of progerin in the cytoplasm and up-regulation of IGF-1R,thereby demonstrating a rejuvenated cellular phenotype and improved mitochondrial function.In vivo,administering an aging cell-adapted siRNA nucleic acid framework delivery system to progerin pathologically expressed premature aging mice(zmpste24^(−/−))can ameliorate the cellular matrix in the nucleus pulposus tissue,effectively delaying IVDD.This study not only identified circATXN1 functioning as a cell senescence promoter in IVDD for the first time,but also successfully demonstrated its therapeutic potential via a tFNA-based siRNA delivery strategy.
基金supported by the Medical and Health Innovation Talent Support Program of Zhejiang Province,China[Grant No.2020RC011]the National Natural Science Foundation of China,China[Grant NO.81772379,81972096,81902238,82002327,82072465 and 82072481].
文摘The current effective method for treatment of spinal cord injury(SCI)is to reconstruct the biological microenvironment by filling the injured cavity area and increasing neuronal differentiation of neural stem cells(NSCs)to repair SCI.However,the method is characterized by several challenges including irregular wounds,and mechanical and electrical mismatch of the material-tissue interface.In the current study,a unique and facile agarose/gelatin/polypyrrole(Aga/Gel/PPy,AGP3)hydrogel with similar conductivity and modulus as the spinal cord was developed by altering the concentration of Aga and PPy.The gelation occurred through non-covalent interactions,and the physically crosslinked features made the AGP3 hydrogels injectable.In vitro cultures showed that AGP3 hydrogel exhibited excellent biocompatibility,and promoted differentiation of NSCs toward neurons whereas it inhibited over-proliferation of astrocytes.The in vivo implanted AGP3 hydrogel completely covered the tissue defects and reduced injured cavity areas.In vivo studies further showed that the AGP3 hydrogel provided a biocompatible microenvironment for promoting endogenous neurogenesis rather than glial fibrosis formation,resulting in significant functional recovery.RNA sequencing analysis further indicated that AGP3 hydrogel significantly modulated expression of neurogenesis-related genes through intracellular Ca2+signaling cascades.Overall,this supramolecular strategy produces AGP3 hydrogel that can be used as favorable biomaterials for SCI repair by filling the cavity and imitating the physiological properties of the spinal cord.
基金This study was supported by grants from the Nature Science Foundation of Zhejiang Province(Y20H060063,LY19H060005,LQ18H060003,LR18E030002,LY18H060004)the Medical and Health Innovation Talent Support Program of Zhejiang Province(2020RC011)+5 种基金the National Natural Science Foundation of China(NO.82072465,NO.81772379,NO.81972096,NO.81902238,NO.21774109,NO.51973188,NO.51522304)the Health Foundation of Zhejiang Province(2018KY092,WKJ-ZJ-1903)the China Postdoctoral Science Foundation(2017M612011)the Zhejiang University Education Foundation Global Partnership Fund,a project supported by the Scientific Research Fund of Zhejiang Provincial Education Department(Y201941476 and Y201941491)Zhejiang Undergraduate Talent Project(grant no.2020R401212)the Scientific Research Fund of Zhejiang Provincial Education Department(Y201941476).
文摘Cell transplantation has been proved the promising therapeutic effects on intervertebral disc degeneration(IVDD).However,the increased levels of reactive oxygen species(ROS)in the degenerated region will impede the efficiency of human adipose-derived stem cells(human ADSCs)transplantation therapy.It inhibits human ADSCs proliferation,and increases human ADSCs apoptosis.Herein,we firstly devised a novel amphiphilic copolymer PEG-PAPO,which could self-assemble into a nanosized micelle and load lipophilic kartogenin(KGN),as a single complex(PAKM).It was an injectable esterase-responsive micelle,and showed controlled release ability of KGN and apocynin(APO).Oxidative stimulation promoted the esterase activity in human ADSCs,which accelerate degradation of esterase-responsive micelle.Compared its monomer,the PAKM micelle possessed better bioactivities,which were attributed to their synergistic effect.It enhanced the viability,autophagic activation(P62,LC3 II),ECM-related transcription factor(SOX9),and ECM(Collagen II,Aggrecan)maintenance in human ADSCs.Furthermore,it is demonstrated that the injection of PAKM with human ADSCs yielded higher disc height and water content in rats.Therefore,PAKM micelles perform promoting cell survival and differentiation effects,and may be a potential therapeutic agent for IVDD.
基金supported by the National Key Research and Development Program of China(2016YFC1200201 to Yuelong Shu)the National Mega-projects for Infectious Diseases(2014ZX10004002002 to Yuelong Shu)the young scientist fund of Chinese Center for Disease Control and Prevention(2016A103 to Wenfei Zhu)
文摘Human influenza viruses preferentially bind to sialic acid-α2,6-galactose (SAα2,6Gal) receptors, which are predominant in human upper respiratory epithelia, whereas avian influenza viruses preferentially bind to SAα2,3Gal receptors. However, variants with amino acid substitutions around the receptor-binding sites of the hemagglutinin (HA) protein can be selected after several passages of human influenza viruses from patients’ respiratory samples in the allantoic cavities of embryonated chicken eggs. In this study, we detected an egg-adapted HA S190R mutation in the pandemic H1N1 virus 2009 (pdmH1N1), and evaluated the effects of this mutation on receptor binding affinity and pathogenicity in mice. Our results revealed that residue 190 is located within the pocket structure of the receptor binding site. The single mutation to arginine at position 190 slightly increased the binding affinity of the virus to the avian receptor and decreased its binding to the long human α2,6-linked sialic acid receptor. Our study demonstrated that the S190R mutation resulted in earlier death and higher weight loss in mice compared with the wild-type virus. Higher viral titers at 1 dpi (days post infection) and diffuse damage at 4 dpi were observed in the lung tissues of mice infected with the mutant virus.
