Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in...Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in mice and determine the underlying mechanism.Methods:First,in vitro cell proliferation and cell cycle of BMMSCs were assessed using a CCK8 assay and flow cytometry,respectively.Osteogenic differentiation was confirmed using staining and quantification of alkaline phosphatase and Alizarin Red S.Next,an osteoporotic mouse model was established by performing bilateral ovariectomy(OVX).Furthermore,the PF4 concentrations were obtained using enzymelinked immunosorbent assay.The bone microarchitecture of the femur was evaluated using microCT and histological analyses.Finally,the key regulators of osteogenesis and pathways were investigated using quantitative real-time polymerase chain reaction and Western blotting.Results:Human PF4 widely and moderately decreased the cell proliferation and osteogenic differentiation ability of BMMSCs.Furthermore,the levels of PF4 in the serum and bone marrow were generally increased,whereas bone microarchitecture deteriorated due to OVX.Moreover,in vivo mouse PF4 supplementation triggered bone deterioration of the femur.In addition,several key regulators of osteogenesis were downregulated,and the integrinα5-focal adhesion kinase-extracellular signalregulated kinase(ITGA5-FAK-ERK)pathway was inhibited due to PF4 supplementation.Conclusions:PF4 may be attributed to OVX-i nduced bone loss triggered by the suppression of bone formation in vivo and alleviate BMMSC osteogenic differentiation by inhibiting the ITGA5-FAK-ERK pathway.展开更多
Peptide-based radiopharmaceuticals targeting integrinα5β1 show promise for precise tumor diagnosis and treatment.However,current peptide-based radioligands that targetα5β1 demonstrate inadequate in vivo performanc...Peptide-based radiopharmaceuticals targeting integrinα5β1 show promise for precise tumor diagnosis and treatment.However,current peptide-based radioligands that targetα5β1 demonstrate inadequate in vivo performance owing to limited tumor retention.The use of PEGylation to enhance the tumor retention of radiopharmaceuticals by prolonging blood circulation time poses a risk of increased blood toxicity.Therefore,a PEGylation strategy that boosts tumor retention while minimizing blood circulation time is urgently needed.Here,we developed a PEGylation-enabled peptide multidisplay platform(PEGibody)for PR_b,anα5β1 targeting peptide.PEGibody generation involved PEGylation and self-assembly.[^(64)Cu]QM-2303 PEGibodies displayed spherical nanoparticles ranging from 100 to 200 nm in diameter.Compared with non-PEGylated radioligands,[^(64)Cu]QM-2303 demonstrated enhanced tumor retention time due to increased binding affinity and stability.Importantly,the biodistribution analysis confirmed rapid clearance of[^(64)Cu]QM-2303 from the bloodstream.Administration of a single dose of[^(177)Lu]QM-2303 led to robust antitumor efficacy.Furthermore,[^(64)Cu]/[^(177)Lu]QM-2303 exhibited low hematological and organ toxicity in both healthy and tumor-bearing mice.Therefore,this study presents a PEGibody-based radiotheranostic approach that enhances tumor retention time and provides long-lasting antitumor effects without prolonging blood circulation lifetime.The PEGibody-based radiopharmaceutical[^(64)Cu]/[^(177)Lu]QM-2303 shows great potential for positron emission tomography imaging-guided targeted radionuclide therapy forα5β1-overexpressing tumors.展开更多
基金Beijing Natural Science Foundation,Grant/Award Number:L222145CAMS Innovation Fund for Medical Sciences,Grant/Award Number:2019-I2M-5-038+2 种基金Clinical Medicine Plus X-Young Scholars Project,Peking Universitythe Fundamental Research Funds for the Central Universities,Grant/Award Number:PKU2023LCXQ017National Natural Science Foundation of China,Grant/Award Number:81700935。
文摘Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in mice and determine the underlying mechanism.Methods:First,in vitro cell proliferation and cell cycle of BMMSCs were assessed using a CCK8 assay and flow cytometry,respectively.Osteogenic differentiation was confirmed using staining and quantification of alkaline phosphatase and Alizarin Red S.Next,an osteoporotic mouse model was established by performing bilateral ovariectomy(OVX).Furthermore,the PF4 concentrations were obtained using enzymelinked immunosorbent assay.The bone microarchitecture of the femur was evaluated using microCT and histological analyses.Finally,the key regulators of osteogenesis and pathways were investigated using quantitative real-time polymerase chain reaction and Western blotting.Results:Human PF4 widely and moderately decreased the cell proliferation and osteogenic differentiation ability of BMMSCs.Furthermore,the levels of PF4 in the serum and bone marrow were generally increased,whereas bone microarchitecture deteriorated due to OVX.Moreover,in vivo mouse PF4 supplementation triggered bone deterioration of the femur.In addition,several key regulators of osteogenesis were downregulated,and the integrinα5-focal adhesion kinase-extracellular signalregulated kinase(ITGA5-FAK-ERK)pathway was inhibited due to PF4 supplementation.Conclusions:PF4 may be attributed to OVX-i nduced bone loss triggered by the suppression of bone formation in vivo and alleviate BMMSC osteogenic differentiation by inhibiting the ITGA5-FAK-ERK pathway.
基金supported by the National Natural Science Foundation of China(No.82372002)the Nonprofit Central Research Institute Fund of the Chinese Academy of Medical Sciences(No.2022-RC350-04,China)+6 种基金the CAMS Innovation Fund for Medical Sciences(Nos.2021-I2M-1-026(2023),2022-I2M-2-002-2,and 2021-I2M-3-001(2023),China)the National Key Research and Development Program of China(No.2022YFE0111700)the Beijing Nova Program to Kuan Hu(No.0104002,China)supported by the Beijing Natural Science Foundation(No.L234044,China)the Fundamental Research Funds for the Central Universities(Nos.3332023044 and 3332023151,China)the CIRP Open Fund of Radiation Protection Laboratories(No.ZHYLYB2021005,China)the China National Nuclear Corporation Young Talent Program.
文摘Peptide-based radiopharmaceuticals targeting integrinα5β1 show promise for precise tumor diagnosis and treatment.However,current peptide-based radioligands that targetα5β1 demonstrate inadequate in vivo performance owing to limited tumor retention.The use of PEGylation to enhance the tumor retention of radiopharmaceuticals by prolonging blood circulation time poses a risk of increased blood toxicity.Therefore,a PEGylation strategy that boosts tumor retention while minimizing blood circulation time is urgently needed.Here,we developed a PEGylation-enabled peptide multidisplay platform(PEGibody)for PR_b,anα5β1 targeting peptide.PEGibody generation involved PEGylation and self-assembly.[^(64)Cu]QM-2303 PEGibodies displayed spherical nanoparticles ranging from 100 to 200 nm in diameter.Compared with non-PEGylated radioligands,[^(64)Cu]QM-2303 demonstrated enhanced tumor retention time due to increased binding affinity and stability.Importantly,the biodistribution analysis confirmed rapid clearance of[^(64)Cu]QM-2303 from the bloodstream.Administration of a single dose of[^(177)Lu]QM-2303 led to robust antitumor efficacy.Furthermore,[^(64)Cu]/[^(177)Lu]QM-2303 exhibited low hematological and organ toxicity in both healthy and tumor-bearing mice.Therefore,this study presents a PEGibody-based radiotheranostic approach that enhances tumor retention time and provides long-lasting antitumor effects without prolonging blood circulation lifetime.The PEGibody-based radiopharmaceutical[^(64)Cu]/[^(177)Lu]QM-2303 shows great potential for positron emission tomography imaging-guided targeted radionuclide therapy forα5β1-overexpressing tumors.
