Formation of graded biomaterials to render shape-morphing scaffolds for 4D biofabrication holds great promise in fabrication of complex structures and the recapitulation of critical dynamics for tissue/organ regenerat...Formation of graded biomaterials to render shape-morphing scaffolds for 4D biofabrication holds great promise in fabrication of complex structures and the recapitulation of critical dynamics for tissue/organ regeneration.Here we describe a facile generation of an adjustable and robust gradient using a single-or multi-material one-step fabrication strategy for 4D biofabrication.By simply photocrosslinking a mixed solution of a photocrosslinkable polymer macromer,photoinitiator(PI),UV absorber and live cells,a cell-laden gradient hydrogel with pre-programmable deformation can be generated.Gradient formation was demonstrated in various polymers including poly(ethylene glycol)(PEG),alginate,and gelatin derivatives using various UV absorbers that present overlap in UV spectrum with that of the PI UV absorbance spectrum.Moreover,this simple and effective method was used as a universal platform to integrate with other hydrogel-engineering techniques such as photomask-aided microfabrication,photo-patterning,ion-transfer printing,and 3D bioprinting to fabricate more advanced cell-laden scaffold structures.Lastly,proof-of-concept 4D tissue engineering was demonstrated in a study of 4D bone-like tissue formation.The strategy’s simplicity along with its versatility paves a new way in solving the hurdle of achieving temporal shape changes in cell-laden single-component hydrogel scaffolds and may expedite the development of 4D biofabricated constructs for biological applications.展开更多
Mitochondria play a crucial role in regulating cellular energy homeostasis and cell death,making them essential organelles.Maintaining proper cellular functions relies on the removal of damaged mitochondria through a ...Mitochondria play a crucial role in regulating cellular energy homeostasis and cell death,making them essential organelles.Maintaining proper cellular functions relies on the removal of damaged mitochondria through a process called mitophagy.Mitophagy is associated with changes in the pH value and has implications for numerous diseases.To effectively monitor mitophagy,fluorescent probes that exhibit high selectivity and sensitivity based on pH detection have emerged as powerful tools.In this review,we present recent advancements in the monitoring of mitophagy using small-molecule fluorescence pH probes.We focus on various sensing mechanisms employed by these probes,including intramolecular charge transfer(ICT),fluorescence resonance energy transfer(FRET),through bond energy transfer(TBET),and photoelectron transfer(PET).Additionally,we discuss disease models used for studying mitophagy and summarize the design requirements for small-molecule fluorescent pH probes suitable for monitoring the mitophagy process.Lastly,we highlight the remaining challenges in this field and propose potential directions for the future development of mitophagy probes.展开更多
Monoamine oxidase A(MAO-A)plays a critical role in the development of glioma and other neurological disorders.Specific analysis of MAO-A activities and its drug interactions in intact tissue is important for biologica...Monoamine oxidase A(MAO-A)plays a critical role in the development of glioma and other neurological disorders.Specific analysis of MAO-A activities and its drug interactions in intact tissue is important for biological and pharmacological research,but highly challenging with current chemical tools.Fluorogenic-inhibitor-based probes offer improved selectivity,sensitivity,and effectiveness to image and profile endogenous targets in an activity-based manner from mammalian cells,which are however rare.Herein,we report HD1 as the first fluorogenic-inhibitor-based probe that can selectively label endogenous MAO-A from various mammalian cells and clinical tissues.The probe was delicately designed based on N-propargyl tetrahydropyridine,a small MAO-A-specific fluorogenic and inhibitory war-head,so that the probe becomes fluorescent upon in situ enzymatic oxidation and covalent labeling of MAO-A.With the excellent binding affinity(in vitro K_(i)=285 n M)and fluorogenic properties,HD1 offers a promising approach to simultaneously image endogenous MAO-A activities by super-resolution fluorescence microscopy and study its drug interactions by subsequent activity-based protein profiling,in both live cells and human glioma tissues.展开更多
基金The authors gratefully acknowledge funding from the National Institutes of Health’s National Institute of Arthritis and Musculoskeletal and Skin Diseases(R01AR069564,and R01AR066193E.A.)+4 种基金National Institute of Biomedical Imaging and Bioengineering(R01EB023907E.A.)and National Heart,Lung,and Blood Institute(T32HL007829R.T.)The contents of this publication are solely the responsibility of the authors and do not necessarily represent the official views of the National Institutes of Health.The authors also thank Susan R.Ross at University of Illinois at Chicago for generously providing the NIH3T3 cells.
文摘Formation of graded biomaterials to render shape-morphing scaffolds for 4D biofabrication holds great promise in fabrication of complex structures and the recapitulation of critical dynamics for tissue/organ regeneration.Here we describe a facile generation of an adjustable and robust gradient using a single-or multi-material one-step fabrication strategy for 4D biofabrication.By simply photocrosslinking a mixed solution of a photocrosslinkable polymer macromer,photoinitiator(PI),UV absorber and live cells,a cell-laden gradient hydrogel with pre-programmable deformation can be generated.Gradient formation was demonstrated in various polymers including poly(ethylene glycol)(PEG),alginate,and gelatin derivatives using various UV absorbers that present overlap in UV spectrum with that of the PI UV absorbance spectrum.Moreover,this simple and effective method was used as a universal platform to integrate with other hydrogel-engineering techniques such as photomask-aided microfabrication,photo-patterning,ion-transfer printing,and 3D bioprinting to fabricate more advanced cell-laden scaffold structures.Lastly,proof-of-concept 4D tissue engineering was demonstrated in a study of 4D bone-like tissue formation.The strategy’s simplicity along with its versatility paves a new way in solving the hurdle of achieving temporal shape changes in cell-laden single-component hydrogel scaffolds and may expedite the development of 4D biofabricated constructs for biological applications.
基金supported by the National Natural Science Foundation of China(22077101,L.L.)Fundamental Research Funds for the Central Universities(L.L.),President Funding of XMU(20720230047,D.A.X.)Startup Program of XMU(D.A.X.and L.L.).
文摘Mitochondria play a crucial role in regulating cellular energy homeostasis and cell death,making them essential organelles.Maintaining proper cellular functions relies on the removal of damaged mitochondria through a process called mitophagy.Mitophagy is associated with changes in the pH value and has implications for numerous diseases.To effectively monitor mitophagy,fluorescent probes that exhibit high selectivity and sensitivity based on pH detection have emerged as powerful tools.In this review,we present recent advancements in the monitoring of mitophagy using small-molecule fluorescence pH probes.We focus on various sensing mechanisms employed by these probes,including intramolecular charge transfer(ICT),fluorescence resonance energy transfer(FRET),through bond energy transfer(TBET),and photoelectron transfer(PET).Additionally,we discuss disease models used for studying mitophagy and summarize the design requirements for small-molecule fluorescent pH probes suitable for monitoring the mitophagy process.Lastly,we highlight the remaining challenges in this field and propose potential directions for the future development of mitophagy probes.
基金supported by the National Key R&D Program of China(2020YFA0709900)the National Natural Science Foundation of China(62288102,22077101,22004099)+3 种基金the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(2020GXLH-Z-008,2020GXLH-Z-021,2020GXLH-Z-023)the Natural Science Foundation of Shaanxi Province(2022JM-130)the Key Research and Development Program of Shaanxi(2020ZDLGY13-04)the Fundamental Research Funds for the Central Universities
文摘Monoamine oxidase A(MAO-A)plays a critical role in the development of glioma and other neurological disorders.Specific analysis of MAO-A activities and its drug interactions in intact tissue is important for biological and pharmacological research,but highly challenging with current chemical tools.Fluorogenic-inhibitor-based probes offer improved selectivity,sensitivity,and effectiveness to image and profile endogenous targets in an activity-based manner from mammalian cells,which are however rare.Herein,we report HD1 as the first fluorogenic-inhibitor-based probe that can selectively label endogenous MAO-A from various mammalian cells and clinical tissues.The probe was delicately designed based on N-propargyl tetrahydropyridine,a small MAO-A-specific fluorogenic and inhibitory war-head,so that the probe becomes fluorescent upon in situ enzymatic oxidation and covalent labeling of MAO-A.With the excellent binding affinity(in vitro K_(i)=285 n M)and fluorogenic properties,HD1 offers a promising approach to simultaneously image endogenous MAO-A activities by super-resolution fluorescence microscopy and study its drug interactions by subsequent activity-based protein profiling,in both live cells and human glioma tissues.
