The intervertebral disc(IVD) is the largest avascular tissue. Hypoxia-inducible factors(HIFs) play essential roles in regulating cellular adaptation in the IVD under physiological conditions. Disc degeneration disease...The intervertebral disc(IVD) is the largest avascular tissue. Hypoxia-inducible factors(HIFs) play essential roles in regulating cellular adaptation in the IVD under physiological conditions. Disc degeneration disease(DDD) is one of the leading causes of disability, and current therapies are ineffective. This study sought to explore the role of HIFs in DDD pathogenesis in mice. The findings of this study showed that among HIF family members, Hif1α was significantly upregulated in cartilaginous endplate(EP) and annulus fibrosus(AF) tissues from human DDD patients and two mouse models of DDD compared with controls. Conditional deletion of the E3 ubiquitin ligase Vhl in EP and AF tissues of adult mice resulted in upregulated Hif1α expression and age-dependent IVD degeneration. Aberrant Hif1α activation enhanced glycolytic metabolism and suppressed mitochondrial function. On the other hand, genetic ablation of the Hif1α gene delayed DDD pathogenesis in Vhl-deficient mice. Administration of 2-methoxyestradiol(2ME2), a selective Hif1α inhibitor, attenuated experimental IVD degeneration in mice. The findings of this study show that aberrant Hif1α activation in EP and AF tissues induces pathological changes in DDD, implying that inhibition of aberrant Hif1α activity is a potential therapeutic strategy for DDD.展开更多
Growing evidences suggest that the fibroblast growth factor/FGF receptor(FGF/FGFR)signaling has crucial roles in a multitude of processes during embryonic development and adult homeostasis by regulating cellular linea...Growing evidences suggest that the fibroblast growth factor/FGF receptor(FGF/FGFR)signaling has crucial roles in a multitude of processes during embryonic development and adult homeostasis by regulating cellular lineage commitment,differentiation,proliferation,and apoptosis of various types of cells.In this review,we provide a comprehensive overview of the current understanding of FGF signaling and its roles in organ development,injury repair,and the pathophysiology of spectrum of diseases,which is a consequence of FGF signaling dysregulation,including cancers and chronic kidney disease(CKD).In this context,the agonists and antagonists for FGF-FGFRs might have therapeutic benefits in multiple systems.展开更多
Cartilage development is controlled by the highly synergistic proliferation and differentiation of growth plate chondrocytes,in which the Indian hedgehog(IHH)and parathyroid hormone-related protein-parathyroid hormone...Cartilage development is controlled by the highly synergistic proliferation and differentiation of growth plate chondrocytes,in which the Indian hedgehog(IHH)and parathyroid hormone-related protein-parathyroid hormone-1 receptor(PTHrP-PTH1R)feedback loop is crucial.The inositol-requiring enzyme 1a/X-box-binding protein-1 spliced(IRE1α/XBP1s)branch of the unfolded protein response(UPR)is essential for normal cartilage development.However,the precise role of ER stress effector IRE1α,encoded by endoplasmic reticulum to nucleus signaling 1(ERN1),in skeletal development remains unknown.Herein,we reported that loss of IRE1α accelerates chondrocyte hypertrophy and promotes endochondral bone growth.ERN1 acts as a negative regulator of chondrocyte proliferation and differentiation in postnatal growth plates.Its deficiency interrupted PTHrP/PTH1R and IHH homeostasis leading to impaired chondrocyte hypertrophy and differentiation.XBP1s,produced by p-IRE1α-mediated splicing,binds and up-regulates PTH1R and IHH,which coordinate cartilage development.Meanwhile,ER stress cannot be activated normally in ERN1-deficient chondrocytes.In conclusion,ERN1 deficiency accelerates chondrocyte hypertrophy and cartilage mineralization by impairing the homeostasis of the IHH and PTHrP/PTH1R feedback loop and ER stress.ERN1 may have a potential role as a new target for cartilage growth and maturation.展开更多
基金supported by grants from the National Key Research and Development Program of China (2018YFA0800802)the National Natural Science Foundation of China (81830075, 81772306, 81530071, and 81991513)the Chongqing Talent Plan (CQYC202001008 and CQYC202005088)
文摘The intervertebral disc(IVD) is the largest avascular tissue. Hypoxia-inducible factors(HIFs) play essential roles in regulating cellular adaptation in the IVD under physiological conditions. Disc degeneration disease(DDD) is one of the leading causes of disability, and current therapies are ineffective. This study sought to explore the role of HIFs in DDD pathogenesis in mice. The findings of this study showed that among HIF family members, Hif1α was significantly upregulated in cartilaginous endplate(EP) and annulus fibrosus(AF) tissues from human DDD patients and two mouse models of DDD compared with controls. Conditional deletion of the E3 ubiquitin ligase Vhl in EP and AF tissues of adult mice resulted in upregulated Hif1α expression and age-dependent IVD degeneration. Aberrant Hif1α activation enhanced glycolytic metabolism and suppressed mitochondrial function. On the other hand, genetic ablation of the Hif1α gene delayed DDD pathogenesis in Vhl-deficient mice. Administration of 2-methoxyestradiol(2ME2), a selective Hif1α inhibitor, attenuated experimental IVD degeneration in mice. The findings of this study show that aberrant Hif1α activation in EP and AF tissues induces pathological changes in DDD, implying that inhibition of aberrant Hif1α activity is a potential therapeutic strategy for DDD.
基金The National Key Research and Development Program of China(2018YFA0800802)National Natural Science Foundation of China(81530071,81772306,81721001,81991513)+1 种基金Innovative Research Team in University(IRT1216)Key research and development projects of science and technology innovation of social undertakings and people’s livelihood security in Chongqing(cstc2017shms-zdyfX0027).
文摘Growing evidences suggest that the fibroblast growth factor/FGF receptor(FGF/FGFR)signaling has crucial roles in a multitude of processes during embryonic development and adult homeostasis by regulating cellular lineage commitment,differentiation,proliferation,and apoptosis of various types of cells.In this review,we provide a comprehensive overview of the current understanding of FGF signaling and its roles in organ development,injury repair,and the pathophysiology of spectrum of diseases,which is a consequence of FGF signaling dysregulation,including cancers and chronic kidney disease(CKD).In this context,the agonists and antagonists for FGF-FGFRs might have therapeutic benefits in multiple systems.
基金supported by the National Natural Science Foundation of China(No.81672209,81871769,82272550)the Chongqing Science and Technology Bureau(China)(No.cstc2021jcyj-bshX0214).
文摘Cartilage development is controlled by the highly synergistic proliferation and differentiation of growth plate chondrocytes,in which the Indian hedgehog(IHH)and parathyroid hormone-related protein-parathyroid hormone-1 receptor(PTHrP-PTH1R)feedback loop is crucial.The inositol-requiring enzyme 1a/X-box-binding protein-1 spliced(IRE1α/XBP1s)branch of the unfolded protein response(UPR)is essential for normal cartilage development.However,the precise role of ER stress effector IRE1α,encoded by endoplasmic reticulum to nucleus signaling 1(ERN1),in skeletal development remains unknown.Herein,we reported that loss of IRE1α accelerates chondrocyte hypertrophy and promotes endochondral bone growth.ERN1 acts as a negative regulator of chondrocyte proliferation and differentiation in postnatal growth plates.Its deficiency interrupted PTHrP/PTH1R and IHH homeostasis leading to impaired chondrocyte hypertrophy and differentiation.XBP1s,produced by p-IRE1α-mediated splicing,binds and up-regulates PTH1R and IHH,which coordinate cartilage development.Meanwhile,ER stress cannot be activated normally in ERN1-deficient chondrocytes.In conclusion,ERN1 deficiency accelerates chondrocyte hypertrophy and cartilage mineralization by impairing the homeostasis of the IHH and PTHrP/PTH1R feedback loop and ER stress.ERN1 may have a potential role as a new target for cartilage growth and maturation.
