Multidrug-resistant Klebsiella pneumoniae(MDR-KP)is characterized by high mortality and risk of nosocomial transmission,and biofilm constitutes the primary challenge in the treatment of its implant-associated and refr...Multidrug-resistant Klebsiella pneumoniae(MDR-KP)is characterized by high mortality and risk of nosocomial transmission,and biofilm constitutes the primary challenge in the treatment of its implant-associated and refractory pulmonary infections.Notably,the hypoxic microenvironment and the physical barrier of biofilm leading to the increased tolerance of the bacteria to antibiotics.Herein,a hypoxia-responsive hybrid nanoparticle(CHLip@FLD/COL)loaded separately with anti-biofilm candidate fingolimod(FLD)and antibiotic colistin(COL)is achieved targeting antibacterial efficacy against MDR-KP in vitro and in vivo.CHLip@FLD/COL is composed of hybridizing hypoxia-responsive lipids(HLipid)and lipid A targeting materials DSPE-mPEG-COL.HLipid is synthesized by hexadecanedioic acid esterified with nitroimidazole,while DSPE-mPEG is coupling with vector COL via amide reaction.The relative level of extracellular polymeric substances and the NIR-IIb sO2 images of the infection site are used as indicators to establish mature biofilm models.CHLip@FLD/COL readily releases FLD and COL in hypoxic conditions,and its MIC against MDR-KP is only one-sixteenth of that when COL is used alone in vitro.The nanoparticle exhibits bacterial targeting ability and antibacterial effect in the pulmonary infection and biofilm infection mice models.Bacterial loads eliminated by 4 Log10 CFU and 2 Log10 CFU,respectively.The strategy provides a valuable reference for the treatment of refractory infections caused by MDR-KP.展开更多
Photoacoustic agents combining photodynamic therapy(PDT) and photothermal therapy(PTT) functions have emerged as potent theranostic agents for combating cancer. The molecular approaches for enhancing the near-infrared...Photoacoustic agents combining photodynamic therapy(PDT) and photothermal therapy(PTT) functions have emerged as potent theranostic agents for combating cancer. The molecular approaches for enhancing the near-infrared(NIR)-absorption and maximizing non-radiative energy transfer are essential for effective photoacoustic imaging(PAI) and therapy applications. In addition, such molecules with high specificity and affinity to cancer cells are urgently needed, which would further decrease the side effect during treatments. In this study, we applied a heavy-atom engineering strategy and introduced p-aminophenol,-thio, and-seleno moieties into NIR heptamethine cyanine(Cy7) skeleton(Cy7-X-NH_(2), X = O, S, Se) to significantly increase photothermal conversion efficiency for PTT and promote intersystem crossing for PDT.Additionally, we designed a series of nitroreductase(NTR)-activated photoacoustic probes(Cy7-X-NO_(2),X = O, S, Se), and target hypoxic tumors with NTR overexpression. Our prostate cancer targeting probe,Cy7-Se-NO_(2)-KUE, exhibited specific tumor photoacoustic signals and effective tumor killing through outstanding synergistic PTT/PDT in vivo. These findings highlighted a versatile strategy for cancer photoacoustic diagnosis and enhanced phototherapy.展开更多
The transcriptional response to low oxygen(hypoxia)in flowering plants is mediated by group VII Ethylene Response Factor(ERFVII)transcription factors,whose proteolysis is oxygen-dependent via the PLANT CYSTEINE OXIDAS...The transcriptional response to low oxygen(hypoxia)in flowering plants is mediated by group VII Ethylene Response Factor(ERFVII)transcription factors,whose proteolysis is oxygen-dependent via the PLANT CYSTEINE OXIDASE(PCO)N-degron pathway.However,when and how this hypoxia response evolved in land plants remains unknown.In this study,we investigated the conservation and divergence of transcriptional responses to hypoxia across major land plant clades.We found that the induction of gene functions associated with glycolysis and fermentation is part of a conserved response across all land plant divisions.Evolutinary analyses suggest that ERFVIIs emerged in the last common ancestor of vascular plants with true roots,coinciding with the evolution of oxygen-dependent destabilization mechanisms that regulate hypoxia-adaptive genes.Proteins from other ERF groups have been independently recruited multiple times in different clades as substrates of the PCO N-degron pathway.Taken together,our results demonstrate that the response of land plants to hypoxia has been refined in derived clades through the evolution of ERFVIIs as transcriptional transducers,which occurred concurrently with the emergence of vascular systems and roots as foraging structures in hypoxic soils.展开更多
Hypoxia is a common characteristic of tumors and associated with poor outcome in most cancer types,thus hypoxia-triggered combined therapeutic systems with well-defined structure hold significant promise for achieving...Hypoxia is a common characteristic of tumors and associated with poor outcome in most cancer types,thus hypoxia-triggered combined therapeutic systems with well-defined structure hold significant promise for achieving specific and effective tumor destruction.Herein,a water-soluble perylene diimide(PDI)cyclophane“Gemini Box”(GBox-1^(4+))is demonstrated as both a hypoxia-responsive photothermal agent and a drug capsule for tumor-specific combination therapy.First,owing to the covalent enclosure of PDI chromophore by double-sided molecular straps,GBox-1^(4+)can significantly stabilize labile PDI radical anions generated through bioreduction at the lesion site of hypoxic tumors,leading to high-efficiency near-infrared photothermal ablation of tumors.Meanwhile,GBox-1^(4+)can act as a molecular capsule to bind water-insoluble antitumor drugs camptothecin and hydroxycamptothecin in 1:1 host-vip stoichiometry with high affinities,greatly enhancing the water solubility of drugs.Eventually,such drug-loading cyclophane system as a hypoxia-activated photothermal/drug combined therapeutic platform exhibits more effective inhibition of tumor growth than the single treatment under identical conditions.This study significantly extends the application range of host-vip cyclophane systems and opens a promising avenue to structurally uniform combined therapeutic agents against hypoxic tumors with improved specificity.展开更多
Nano-drug delivery systems(nanoDDS)have been extensively investigated clinically to improve the therapeutic effect of anticancer drugs.However,the complicated synthesis during the preparation as well as the potential ...Nano-drug delivery systems(nanoDDS)have been extensively investigated clinically to improve the therapeutic effect of anticancer drugs.However,the complicated synthesis during the preparation as well as the potential drug leakage during transportation has greatly limited their general application.In this work,a calixarene-integrated nanoDDS(CanD)that achieves tumor-targeted delivery and tracking of anti-cancer drugs in vivo is presented.The hypoxia-responsive calixarene(SAC4A)exhibits high binding affinity to a series of anti-cancer drugs and rhodamine B(RhB)under normoxic condition while decreasing the binding affinity under hypoxic condition,which leads to the drug release and fluorescence recovery simultaneously.Furthermore,the hypoxia-responsiveness of SAC4A conveys CanD with tumor-targeting ability,resulting in the enrichment of the drug in tumors and enhancement in tumor suppression in mice.Moreover,CanD could become a general platform allowing the delivery of a wide scope of anti-cancer drugs that have strong host-vip interaction with SAC4A.展开更多
The success of gene therapy depends largely on the efficacy of gene delivery vector systems that can deliver genes to target organs or cells selectively and efficiently with minimal toxicity.Here,we show that by using...The success of gene therapy depends largely on the efficacy of gene delivery vector systems that can deliver genes to target organs or cells selectively and efficiently with minimal toxicity.Here,we show that by using the HRE.ppET-1 regulatory element,we were able to restrict expression of the transgene of vascular endothelial growth factor(VEGF)to endothelial cells exclusively in hypoxic conditions.Eukaryotic expression vectors such as pEGFP-HRE.ppET-1,pcDNA3.1-VEGF+Pa,pcDNA3.1-ppET-1+EGF+Pa,and pcDNA3.1-HRE.ppET-1+VEGF+Pa were constructed by using a series of nuclear molecule handling methods like PCR,enzyme digestion.The recombinant vectors were transfected into HUVEC cells and HL7702 cells by the lipofectin method.GFP expression was observed with a fluorescence microscope to validate the specificity of expression in endothelial cells under the regulation of HRE.ppET-1 element.Cobalt chloride(final concentration 100μmol/L)was added to the medium to mimic hypoxia in vitro.After transfection of vectors,the expression of VEGF mRNA was detected by RT-PCR,and the expression of VEGF was detected by Western blotting and ELISA methods under normoxia and hypoxia,respectively.The cell proliferation rate was detected by the MTT test.The ex-pression of GFP revealed that the exterior gene was transcripted effectively in endothelial cells regu-lated by the HRE.ppET-1 element,while the expression of GFP was very weak in nonendothelial cells.The results of RT-PCR,Western blotting and ELISA showed that VEGF gene expression in the pcDNA3.1-HRE.ppET-1+VEGF+Pa group and in the pcDNA3.1-ppET-1+VEGF+Pa group was higher in hypoxia than it was in normoxia(P<0.05).The MTT test showed that the proliferation rate of HUVEC transfected with HPVA under hypoxia exceeded that of the control group.We conclude that the HRE.ppET-1 element was expressed specifically in endothelial cells,and can increase the expression of VEGF in hypoxia and stimulate proliferation of endothelial cells.Taking advantage of these facts could greatly improve the efficiency of gene therapy.The vector would be valuable for various gene transfer studies targeting endothelial cells.展开更多
基金granted by National Key Research and Development Program of China(2021YFD1800900)Science and Technology Innovation Key R&D Program of Chongqing(CSTB2024TIAD-STX0038)+3 种基金National Natural Science Foundation of China(82574334,32501226)Chongqing Science and Technology Commission(CSTB2023NSCQ-JQX0002)Special Fund for Youth Team of Southwest University(SWU-XJLJ202306)Chongqing Natural Science Foundation(CSTB2024NSCQ-MSX0547).
文摘Multidrug-resistant Klebsiella pneumoniae(MDR-KP)is characterized by high mortality and risk of nosocomial transmission,and biofilm constitutes the primary challenge in the treatment of its implant-associated and refractory pulmonary infections.Notably,the hypoxic microenvironment and the physical barrier of biofilm leading to the increased tolerance of the bacteria to antibiotics.Herein,a hypoxia-responsive hybrid nanoparticle(CHLip@FLD/COL)loaded separately with anti-biofilm candidate fingolimod(FLD)and antibiotic colistin(COL)is achieved targeting antibacterial efficacy against MDR-KP in vitro and in vivo.CHLip@FLD/COL is composed of hybridizing hypoxia-responsive lipids(HLipid)and lipid A targeting materials DSPE-mPEG-COL.HLipid is synthesized by hexadecanedioic acid esterified with nitroimidazole,while DSPE-mPEG is coupling with vector COL via amide reaction.The relative level of extracellular polymeric substances and the NIR-IIb sO2 images of the infection site are used as indicators to establish mature biofilm models.CHLip@FLD/COL readily releases FLD and COL in hypoxic conditions,and its MIC against MDR-KP is only one-sixteenth of that when COL is used alone in vitro.The nanoparticle exhibits bacterial targeting ability and antibacterial effect in the pulmonary infection and biofilm infection mice models.Bacterial loads eliminated by 4 Log10 CFU and 2 Log10 CFU,respectively.The strategy provides a valuable reference for the treatment of refractory infections caused by MDR-KP.
基金partially supported by the National Key R&D Program of China (No.2022YFE0199700)the National Natural Science Foundation of China (NSFC) projects (Nos.22077139and 22122705)CAMS Innovation Fund for Medical Sciences(CIFMS)(No.2022-I2M-2–002)。
文摘Photoacoustic agents combining photodynamic therapy(PDT) and photothermal therapy(PTT) functions have emerged as potent theranostic agents for combating cancer. The molecular approaches for enhancing the near-infrared(NIR)-absorption and maximizing non-radiative energy transfer are essential for effective photoacoustic imaging(PAI) and therapy applications. In addition, such molecules with high specificity and affinity to cancer cells are urgently needed, which would further decrease the side effect during treatments. In this study, we applied a heavy-atom engineering strategy and introduced p-aminophenol,-thio, and-seleno moieties into NIR heptamethine cyanine(Cy7) skeleton(Cy7-X-NH_(2), X = O, S, Se) to significantly increase photothermal conversion efficiency for PTT and promote intersystem crossing for PDT.Additionally, we designed a series of nitroreductase(NTR)-activated photoacoustic probes(Cy7-X-NO_(2),X = O, S, Se), and target hypoxic tumors with NTR overexpression. Our prostate cancer targeting probe,Cy7-Se-NO_(2)-KUE, exhibited specific tumor photoacoustic signals and effective tumor killing through outstanding synergistic PTT/PDT in vivo. These findings highlighted a versatile strategy for cancer photoacoustic diagnosis and enhanced phototherapy.
基金supported by a Leverhulme Trust Research Project Grant(RPG-2017-132)to M.J.H.the European Research Council(ERC,grant agreement no.101001320,“Synoxys”)+1 种基金the Italian Ministry of University and Research(MIUR,PRIN grant no.20173EWRT9)the Biotechnology and Biological Sciences Research Council(BB/X001059/1)to F.L.
文摘The transcriptional response to low oxygen(hypoxia)in flowering plants is mediated by group VII Ethylene Response Factor(ERFVII)transcription factors,whose proteolysis is oxygen-dependent via the PLANT CYSTEINE OXIDASE(PCO)N-degron pathway.However,when and how this hypoxia response evolved in land plants remains unknown.In this study,we investigated the conservation and divergence of transcriptional responses to hypoxia across major land plant clades.We found that the induction of gene functions associated with glycolysis and fermentation is part of a conserved response across all land plant divisions.Evolutinary analyses suggest that ERFVIIs emerged in the last common ancestor of vascular plants with true roots,coinciding with the evolution of oxygen-dependent destabilization mechanisms that regulate hypoxia-adaptive genes.Proteins from other ERF groups have been independently recruited multiple times in different clades as substrates of the PCO N-degron pathway.Taken together,our results demonstrate that the response of land plants to hypoxia has been refined in derived clades through the evolution of ERFVIIs as transcriptional transducers,which occurred concurrently with the emergence of vascular systems and roots as foraging structures in hypoxic soils.
基金supported by the National Natural Science Foundation of China (22171021 and 22322403)the Beijing Natural Science Foundation (2232027 and 2242004)the China Postdoctoral Science Foundation (2023M730245)。
文摘Hypoxia is a common characteristic of tumors and associated with poor outcome in most cancer types,thus hypoxia-triggered combined therapeutic systems with well-defined structure hold significant promise for achieving specific and effective tumor destruction.Herein,a water-soluble perylene diimide(PDI)cyclophane“Gemini Box”(GBox-1^(4+))is demonstrated as both a hypoxia-responsive photothermal agent and a drug capsule for tumor-specific combination therapy.First,owing to the covalent enclosure of PDI chromophore by double-sided molecular straps,GBox-1^(4+)can significantly stabilize labile PDI radical anions generated through bioreduction at the lesion site of hypoxic tumors,leading to high-efficiency near-infrared photothermal ablation of tumors.Meanwhile,GBox-1^(4+)can act as a molecular capsule to bind water-insoluble antitumor drugs camptothecin and hydroxycamptothecin in 1:1 host-vip stoichiometry with high affinities,greatly enhancing the water solubility of drugs.Eventually,such drug-loading cyclophane system as a hypoxia-activated photothermal/drug combined therapeutic platform exhibits more effective inhibition of tumor growth than the single treatment under identical conditions.This study significantly extends the application range of host-vip cyclophane systems and opens a promising avenue to structurally uniform combined therapeutic agents against hypoxic tumors with improved specificity.
基金National Key Research and Development Programs of China(No.2018YFA0209700)National Natural Science Foundation of China(NSFC,No.22077073)+1 种基金Frontiers Science Center for New Organic Matter(No.63181206)Fundamental Research Funds for the Central Universities(Nankai University,No.63206015).
文摘Nano-drug delivery systems(nanoDDS)have been extensively investigated clinically to improve the therapeutic effect of anticancer drugs.However,the complicated synthesis during the preparation as well as the potential drug leakage during transportation has greatly limited their general application.In this work,a calixarene-integrated nanoDDS(CanD)that achieves tumor-targeted delivery and tracking of anti-cancer drugs in vivo is presented.The hypoxia-responsive calixarene(SAC4A)exhibits high binding affinity to a series of anti-cancer drugs and rhodamine B(RhB)under normoxic condition while decreasing the binding affinity under hypoxic condition,which leads to the drug release and fluorescence recovery simultaneously.Furthermore,the hypoxia-responsiveness of SAC4A conveys CanD with tumor-targeting ability,resulting in the enrichment of the drug in tumors and enhancement in tumor suppression in mice.Moreover,CanD could become a general platform allowing the delivery of a wide scope of anti-cancer drugs that have strong host-vip interaction with SAC4A.
基金the National Natural Science Foundation of China(Grant No.30500541)
文摘The success of gene therapy depends largely on the efficacy of gene delivery vector systems that can deliver genes to target organs or cells selectively and efficiently with minimal toxicity.Here,we show that by using the HRE.ppET-1 regulatory element,we were able to restrict expression of the transgene of vascular endothelial growth factor(VEGF)to endothelial cells exclusively in hypoxic conditions.Eukaryotic expression vectors such as pEGFP-HRE.ppET-1,pcDNA3.1-VEGF+Pa,pcDNA3.1-ppET-1+EGF+Pa,and pcDNA3.1-HRE.ppET-1+VEGF+Pa were constructed by using a series of nuclear molecule handling methods like PCR,enzyme digestion.The recombinant vectors were transfected into HUVEC cells and HL7702 cells by the lipofectin method.GFP expression was observed with a fluorescence microscope to validate the specificity of expression in endothelial cells under the regulation of HRE.ppET-1 element.Cobalt chloride(final concentration 100μmol/L)was added to the medium to mimic hypoxia in vitro.After transfection of vectors,the expression of VEGF mRNA was detected by RT-PCR,and the expression of VEGF was detected by Western blotting and ELISA methods under normoxia and hypoxia,respectively.The cell proliferation rate was detected by the MTT test.The ex-pression of GFP revealed that the exterior gene was transcripted effectively in endothelial cells regu-lated by the HRE.ppET-1 element,while the expression of GFP was very weak in nonendothelial cells.The results of RT-PCR,Western blotting and ELISA showed that VEGF gene expression in the pcDNA3.1-HRE.ppET-1+VEGF+Pa group and in the pcDNA3.1-ppET-1+VEGF+Pa group was higher in hypoxia than it was in normoxia(P<0.05).The MTT test showed that the proliferation rate of HUVEC transfected with HPVA under hypoxia exceeded that of the control group.We conclude that the HRE.ppET-1 element was expressed specifically in endothelial cells,and can increase the expression of VEGF in hypoxia and stimulate proliferation of endothelial cells.Taking advantage of these facts could greatly improve the efficiency of gene therapy.The vector would be valuable for various gene transfer studies targeting endothelial cells.
