Parthenogenetic embryonic stem （pES） cells provide a valuable in vitro model system for studying the molecular mechanisms that underlie genomic imprinting. However, the pluripotency of pES cells and the expression p...Parthenogenetic embryonic stem （pES） cells provide a valuable in vitro model system for studying the molecular mechanisms that underlie genomic imprinting. However, the pluripotency of pES cells and the expression profiles of paternally expressed imprinted genes have not been fully explored. In this study, three mouse pES cell lines were established and the differentiation potential of these cells in extended culture was evaluated. The undifferentiated cells had a normal karyotype and homozygous genome, and expressed ES-cell-specific molecular markers. The cells remained undifferentiated after more than 50 passages and exhibited pluripotent differentiation capacity. All three lines of the established ES cells produced teratomas; two lines of ES cells produced chimeras and germline transmission. Furthermore, activation of the paternally expressed imprinted genes Snrpn, U2afl-rsl, Peg3, Impact, Zfp127, Dlkl and Mest in these cells was detected. Some paternally expressed imprinted genes were found to be expressed in the blastocyst stage of parthenogenetically activated embryos in vitro and their expression level increased with extended pES cell culture. Furthermore, our data show that the activation of these paternally expressed imprinted genes in pES cells was associated with a change in the methylation of the related differentially methylated regions. These findings provide direct evidence for the pluripotency of pES cells and demonstrate the association between the DNA methylation pattern and the activa- tion of paternally expressed imprinted genes in pES cells. Thus, the established ES cell lines provide a valuable model for studying epigenetic regulation in mammalian development.展开更多
The TET family is well known for active DNA demethylation and plays important roles in regulating transcription,the epigenome and development.Nevertheless,previous studies using knockdown(KD)or knockout(KO)models to i...The TET family is well known for active DNA demethylation and plays important roles in regulating transcription,the epigenome and development.Nevertheless,previous studies using knockdown(KD)or knockout(KO)models to investigate the function of TET have faced challenges in distinguishing its enzymatic and nonenzymatic roles,as well as compensatory effects among TET family members,which has made the understanding of the enzymatic role of TET not accurate enough.To solve this problem,we successfully generated mice catalytically inactive for specific Tet members(Tetm/m).We observed that,compared with the reported KO mice,mutant mice exhibited distinct developmental defects,including growth retardation,sex imbalance,infertility,and perinatal lethality.Notably,Tetm/mmouse embryonic stem cells(mESCs)were successfully established but entered an impaired developmental program,demonstrating extended pluripotency and defects in ectodermal differentiation caused by abnormal DNA methylation.Intriguingly,Tet3,traditionally considered less critical for m ESCs due to its lower expression level,had a significant impact on the global hydroxymethylation,gene expression,and differentiation potential of mESCs.Notably,there were common regulatory regions between Tet1 and Tet3 in pluripotency regulation.In summary,our study provides a more accurate reference for the functional mechanism of Tet hydroxymethylase activity in mouse development and ESC pluripotency regulation.展开更多
Wholly defined ex vivo expansion conditions for biliary tree stem cell(BTSC)organoids were established,consisting of a defined proliferative medium(DPM)used in combination with soft hyaluronan hydrogels.The DPM consis...Wholly defined ex vivo expansion conditions for biliary tree stem cell(BTSC)organoids were established,consisting of a defined proliferative medium(DPM)used in combination with soft hyaluronan hydrogels.The DPM consisted of commercially available Kubota's Medium(KM),to which a set of small molecules,particular paracrine signals,and heparan sulfate(HS)were added.The small molecules used were DNA methyltransferase inhibitor(RG108),TGF-βType I receptor inhibitor(A83-01),adenylate cyclase activator(Forskolin),and L-type Ca2+channel agonist(Bay K8644).A key paracrine signal proved to be R-spondin 1(RSPO1),a secreted protein that activates Wnts.Soluble hyaluronans,0.05%sodium hyaluronate,were used with DPM to expand monolayer cultures.Expansion of organoids was achieved by using DPM in combination with embedding organoids in Matrigel that was replaced with a defined thiol-hyaluronan triggered with PEGDA to form a hydrogel with a rheology[G*]of less than 100 Pa.The combination is called the BTSC-Expansion-Glycogel-System(BEX-gel system)for expanding BTSCs as a monolayer or as organoids.The BTSC organoids were expanded more than 3000-fold ex vivo in the BEX-gel system within 70 days while maintaining phenotypic traits indicative of stem/progenitors.Stem-cell-patch grafting of expanded BTSC organoids was performed on the livers of Fah-/-mice with tyrosinemia and resulted in the rescue of the mice and restoration of their normal liver functions.The BEX-gel system for BTSC organoid expansion provides a strategy to generate sufficient numbers of organoids for the therapeutic treatments of liver diseases.展开更多
Fibroblast activation protein(Fap)is a serine protease that degrades denatured type I collagen,α2-antiplasmin and FGF21.Fap is highly expressed in bone marrow stromal cells and functions as an osteogenic suppressor a...Fibroblast activation protein(Fap)is a serine protease that degrades denatured type I collagen,α2-antiplasmin and FGF21.Fap is highly expressed in bone marrow stromal cells and functions as an osteogenic suppressor and can be inhibited by the bone growth factor Osteolectin(Oln).Fap is also expressed in synovial fibroblasts and positively correlated with the severity of rheumatoid arthritis(RA).However,whether Fap plays a critical role in osteoarthritis(OA)remains poorly understood.Here,we found that Fap is significantly elevated in osteoarthritic synovium,while the genetic deletion or pharmacological inhibition of Fap significantly ameliorated posttraumatic OA in mice.Mechanistically,we found that Fap degrades denatured type II collagen(Col II)and Mmp13-cleaved native Col II.Intra-articular injection of r Fap significantly accelerated Col II degradation and OA progression.In contrast,Oln is expressed in the superficial layer of articular cartilage and is significantly downregulated in OA.Genetic deletion of Oln significantly exacerbated OA progression,which was partially rescued by Fap deletion or inhibition.Intra-articular injection of r Oln significantly ameliorated OA progression.Taken together,these findings identify Fap as a critical pathogenic factor in OA that could be targeted by both synthetic and endogenous inhibitors to ameliorate articular cartilage degradation.展开更多
diabetes mellitus(DM)is a disease syndrome characterized by chronic hyperglycaemia.A long-term high-glucose environment leads to reactive oxygen species(ROS)production and nuclear DNA damage.human umbilical cord mesen...diabetes mellitus(DM)is a disease syndrome characterized by chronic hyperglycaemia.A long-term high-glucose environment leads to reactive oxygen species(ROS)production and nuclear DNA damage.human umbilical cord mesenchymal stem cell(HUcMSC)infusion induces significant antidiabetic effects in type 2 diabetes mellitus(T2DM)rats.Insulin-like growth factor 1(IGF1)receptor(IGF1R)is important in promoting glucose metabolism in diabetes;however,the mechanism by which HUcMSC can treat diabetes through IGF1R and DNA damage repair remains unclear.In this study,a DM rat model was induced with high-fat diet feeding and streptozotocin(STZ)administration and rats were infused four times with HUcMSC.Blood glucose,interleukin-6(IL-6),IL-10,glomerular basement membrane,and renal function were examined.Proteins that interacted with IGF1R were determined through coimmunoprecipitation assays.The expression of IGF1R,phosphorylated checkpoint kinase 2(p-CHK2),and phosphorylated protein 53(p-p53)was examined using immunohistochemistry(IHC)and western blot analysis.Enzyme-linked immunosorbent assay(ELISA)was used to determine the serum levels of 8-hydroxydeoxyguanosine(8-OHdG).Flow cytometry experiments were used to detect the surface markers of HUcMSC.The identification of the morphology and phenotype of HUcMSC was performed by way of oil red“O”staining and Alizarin red staining.DM rats exhibited abnormal blood glucose and IL-6/10 levels and renal function changes in the glomerular basement membrane,increased the expression of IGF1 and IGF1R.IGF1R interacted with CHK2,and the expression of p-CHK2 was significantly decreased in IGF1R-knockdown cells.When cisplatin was used to induce DNA damage,the expression of p-CHK2 was higher than that in the IGF1R-knockdown group without cisplatin treatment.HUcMSC infusion ameliorated abnormalities and preserved kidney structure and function in DM rats.The expression of IGF1,IGF1R,p-CHK2,and p-p53,and the level of 8-OHdG in the DM group increased significantly compared with those in the control group,and decreased after HUcMSC treatment.Our results suggested that IGF1R could interact with CHK2 and mediate DNA damage.HUcMSC infusion protected against kidney injury in DM rats.The underlying mechanisms may include HUcMSC-mediated enhancement of diabetes treatment via the IGF1R-CHK2-p53 signalling pathway.展开更多
In growing children,growth plate cartilage has limited self-repair ability upon fracture injury always leading to limb growth arrest.Interestingly,one type of fracture injuries within the growth plate achieve amazing ...In growing children,growth plate cartilage has limited self-repair ability upon fracture injury always leading to limb growth arrest.Interestingly,one type of fracture injuries within the growth plate achieve amazing self-healing,however,the mechanism is unclear.Using this type of fracture mouse model,we discovered the activation of Hedgehog(Hh)signaling in the injured growth plate,which could activate chondrocytes in growth plate and promote cartilage repair.展开更多
The liver has a complex cellular composition and a remarkable regenerative capacity.The primary cell types in the liver are two parenchymal cell populations,hepatocytes and cholangiocytes,that perform most of the func...The liver has a complex cellular composition and a remarkable regenerative capacity.The primary cell types in the liver are two parenchymal cell populations,hepatocytes and cholangiocytes,that perform most of the functions of the liver and that are helped through interactions with non-parenchymal cell types comprising stellate cells,endothelia and various hemopoietic cell populations.The regulation of the cells in the liver is mediated by an insoluble complex of proteins and carbohydrates,the extracellular matrix,working synergistically with soluble paracrine and systemic signals.In recent years,with the rapid development of genetic sequencing technologies,research on the liver’s cellular composition and its regulatory mechanisms during various conditions has been extensively explored.Meanwhile breakthroughs in strategies for cell transplantation are enabling a future in which there can be a rescue of patients with end-stage liver diseases,offering potential solutions to the chronic shortage of livers and alternatives to liver transplantation.This review will focus on the cellular mechanisms of liver homeostasis and how to select ideal sources of cells to be transplanted to achieve liver regeneration and repair.Recent advances are summarized for promoting the treatment of end-stage liver diseases by forms of cell transplantation that now include grafting strategies.展开更多
Dear Editor,Myocardial infarction is one of the leading causes of morbidity and mortality.Stem/progenitor cells therapy has emerged as a promising strategy for the cardiac repair,especially those derived from cardiac ...Dear Editor,Myocardial infarction is one of the leading causes of morbidity and mortality.Stem/progenitor cells therapy has emerged as a promising strategy for the cardiac repair,especially those derived from cardiac tissue,have attracted worldwide attention(Tompkins et al.,2018).However,challenges and controversies remain in characterizing functional progenitors and explaining their mechanisms of action.展开更多
Spinal cord injury(SCI)is a severe damage usually leading to limb dysesthesia,motor dysfunction,and other physiological disability.We have previously shown that NT3-chitosan could trigger an acute SCI repairment in ra...Spinal cord injury(SCI)is a severe damage usually leading to limb dysesthesia,motor dysfunction,and other physiological disability.We have previously shown that NT3-chitosan could trigger an acute SCI repairment in rats and non-human primates.Due to the negative effect of inhibitory molecules in glial scar on axonal regeneration,however,the role of NT3-chitosan in the treatment of chronic SCI remains unclear.Compared with the fresh wound of acute SCI,how to handle the lesion core and glial scars is a major issue related to chronic-SCI repair.Here we report,in a chronic complete SCI rat model,establishment of magnetic resonancediffusion tensor imaging(MR-DTI)methods to monitor spatial and temporal changes of the lesion area,which matched well with anatomical analyses.Clearance of the lesion core via suction of cystic tissues and trimming of solid scar tissues before introducing NT3-chitosan using either a rigid tubular scaffold or a soft gel form led to robust neural regeneration,which interconnected the severed ascending and descending axons and accompanied with electrophysiological and motor functional recovery.In contrast,cystic tissue extraction without scar trimming followed by NT3-chitosan injection,resulted in little,if any regeneration.Taken together,after lesion core clearance,NT3-chitosan can be used to enable chronic-SCI repair and MR-DTI-based mapping of lesion area and monitoring of ongoing regeneration can potentially be implemented in clinical studies for subacute/chronic-SCI repair.展开更多
Rett syndrome(RTT)is a progressive neurodevelop-mental disorder,mainly caused by mutations in MeCP2 and currently with no cure.We report here that neurons from R106W MeCP2 RTT human iPSCs as well as human embryonic st...Rett syndrome(RTT)is a progressive neurodevelop-mental disorder,mainly caused by mutations in MeCP2 and currently with no cure.We report here that neurons from R106W MeCP2 RTT human iPSCs as well as human embryonic stem cells after MeCP2 knockdown exhibit consistent and long-lasting impairment in maturation as indicated by impaired action potentials and passive membrane properties as well as reduced soma size and spine density.Moreover,RTT-inherent defects in neuronal maturation could be pan-neuronal and occurred in neurons with both dorsal and ventral forebrain features.Knockdown of MeCP2 led to more severe neuronal deficits as compared to RTT iPSC-derived neurons,which appeared to retain partial function.Strikingly,consistent deficits in nuclear size,dendritic complexity and circuitry-dependent spontaneous postsynaptic currents could only be observed in MeCP2 knockdown neurons but not RTT iPSC-derived neurons.Both neuron-intrinsic and circuitry-dependent deficits of MeCP2-deficient neurons could be fully or partially rescued by re-expression of wild type or T158M MeCP2,strengthening the dosage dependency of MeCP2 on disease phenotypes and also the partial function of the mutant.Our findings thus reveal stable neuronal maturation deficits and unexpectedly,graded sensitivities of neuron-inherent and neural transmission phenotypes towards the extent of MeCP2 deficiency,which is informative for future therapeutic development.展开更多
Ischemic heart disease is one of the main causes of morbidity and mortality in the world. In adult mammalianhearts, most cardiomyocytes are terminally differentiated and have extremely limited capacity of proliferatio...Ischemic heart disease is one of the main causes of morbidity and mortality in the world. In adult mammalianhearts, most cardiomyocytes are terminally differentiated and have extremely limited capacity of proliferation,making it impossible to regenerate the heart after injuries such as myocardial infarction. MicroRNAs (miRNAs), aclass of non-coding single-stranded RNA, which are involved in mRNA silencing and the regulation of posttranscriptionalgene expression, have been shown to play a crucial role in cardiac development and cardiomyocyteproliferation. Muscle specific miRNAs such as miR-1 are key regulators of cardiomyocyte maturation and growth,while miR-199-3p and other miRNAs display potent activity to induce proliferation of cardiomyocytes. Given theirsmall size and relative pleiotropic effects, miRNAs have gained significant attraction as promising therapeutic targetsor tools in cardiac regeneration. Increasing number of studies demonstrated that overexpression or inhibition ofspecific miRNAs could induce cardiomyocyte proliferation and cardiac regeneration. Some common targets of proproliferationmiRNAs, such as the Hippo-Yap signaling pathway, were identified in multiple species, highlighting thepower of miRNAs as probes to dissect core regulators of biological processes. A number of miRNAs have beenshown to improve heart function after myocardial infarction in mice, and one trial in swine also demonstratedpromising outcomes. However, technical difficulties, especially in delivery methods, and adverse effects, such asuncontrolled proliferation, remain. In this review, we summarize the recent progress in miRNA research in cardiacdevelopment and regeneration, examine the mechanisms of miRNA regulating cardiomyocyte proliferation, anddiscuss its potential as a new strategy for cardiac regeneration therapy.展开更多
Congenital hydrocephalus is a major neurological disorder with high rates of morbidity and mortality;however,the underlying cellular and molecular mechanisms remain largely unknown.Reproducible animal models mirroring...Congenital hydrocephalus is a major neurological disorder with high rates of morbidity and mortality;however,the underlying cellular and molecular mechanisms remain largely unknown.Reproducible animal models mirroring both embryonic and postnatal hydrocephalus are also limited.Here,we describe a new mouse model of congenital hydrocephalus through knockout ofβ-catenin in Nkx2.1-expressing regional neural progenitors.Progressive ventriculomegaly and an enlarged brain were consistently observed in knockout mice from embryonic day 12.5 through to adulthood.Transcriptome profiling revealed severe dysfunctions in progenitor maintenance in the ventricular zone and therefore in cilium biogenesis afterβ-catenin knockout.Histological analyses also revealed an aberrant neuronal layout in both the ventral and dorsal telencephalon in hydrocephalic mice at both embryonic and postnatal stages.Thus,knockout ofβ-catenin in regional neural progenitors leads to congenital hydrocephalus and provides a reproducible animal model for studying pathological changes and developing therapeutic interventions for this devastating disease.展开更多
文摘Parthenogenetic embryonic stem （pES） cells provide a valuable in vitro model system for studying the molecular mechanisms that underlie genomic imprinting. However, the pluripotency of pES cells and the expression profiles of paternally expressed imprinted genes have not been fully explored. In this study, three mouse pES cell lines were established and the differentiation potential of these cells in extended culture was evaluated. The undifferentiated cells had a normal karyotype and homozygous genome, and expressed ES-cell-specific molecular markers. The cells remained undifferentiated after more than 50 passages and exhibited pluripotent differentiation capacity. All three lines of the established ES cells produced teratomas; two lines of ES cells produced chimeras and germline transmission. Furthermore, activation of the paternally expressed imprinted genes Snrpn, U2afl-rsl, Peg3, Impact, Zfp127, Dlkl and Mest in these cells was detected. Some paternally expressed imprinted genes were found to be expressed in the blastocyst stage of parthenogenetically activated embryos in vitro and their expression level increased with extended pES cell culture. Furthermore, our data show that the activation of these paternally expressed imprinted genes in pES cells was associated with a change in the methylation of the related differentially methylated regions. These findings provide direct evidence for the pluripotency of pES cells and demonstrate the association between the DNA methylation pattern and the activa- tion of paternally expressed imprinted genes in pES cells. Thus, the established ES cell lines provide a valuable model for studying epigenetic regulation in mammalian development.
基金supported by the National Key Research and Development Program of China(2020YFA0112500,2021YFA1100300,2021YFC2700300 and 2022YFC2702200)supported by the Fundamental Research Funds for the Central Universities+2 种基金National Natural Science Foundation of China(32070857 and 32270856,and 32270858)the Science and Technology Commission of Shanghai Municipality(23JC1403700)Peak Disciplines(TypeⅣ)of Institutions of Higher Learning in Shanghai。
文摘The TET family is well known for active DNA demethylation and plays important roles in regulating transcription,the epigenome and development.Nevertheless,previous studies using knockdown(KD)or knockout(KO)models to investigate the function of TET have faced challenges in distinguishing its enzymatic and nonenzymatic roles,as well as compensatory effects among TET family members,which has made the understanding of the enzymatic role of TET not accurate enough.To solve this problem,we successfully generated mice catalytically inactive for specific Tet members(Tetm/m).We observed that,compared with the reported KO mice,mutant mice exhibited distinct developmental defects,including growth retardation,sex imbalance,infertility,and perinatal lethality.Notably,Tetm/mmouse embryonic stem cells(mESCs)were successfully established but entered an impaired developmental program,demonstrating extended pluripotency and defects in ectodermal differentiation caused by abnormal DNA methylation.Intriguingly,Tet3,traditionally considered less critical for m ESCs due to its lower expression level,had a significant impact on the global hydroxymethylation,gene expression,and differentiation potential of mESCs.Notably,there were common regulatory regions between Tet1 and Tet3 in pluripotency regulation.In summary,our study provides a more accurate reference for the functional mechanism of Tet hydroxymethylase activity in mouse development and ESC pluripotency regulation.
基金Major Program of National Key Research and Development Project(2020YFA0112600,2019YFA0801502)National Natural Science Foundation of China(82173019,82270638,8220374,82300718)+1 种基金Project of Shanghai Science and Technology Commission(22ZR1451100,22Y11908500)Peak Disciplines(Type IV)of Institutions of Higher Learning in Shanghai,and Shanghai Engineering Research Center of Stem Cells Translational Medicine(20DZ2255100).
文摘Wholly defined ex vivo expansion conditions for biliary tree stem cell(BTSC)organoids were established,consisting of a defined proliferative medium(DPM)used in combination with soft hyaluronan hydrogels.The DPM consisted of commercially available Kubota's Medium(KM),to which a set of small molecules,particular paracrine signals,and heparan sulfate(HS)were added.The small molecules used were DNA methyltransferase inhibitor(RG108),TGF-βType I receptor inhibitor(A83-01),adenylate cyclase activator(Forskolin),and L-type Ca2+channel agonist(Bay K8644).A key paracrine signal proved to be R-spondin 1(RSPO1),a secreted protein that activates Wnts.Soluble hyaluronans,0.05%sodium hyaluronate,were used with DPM to expand monolayer cultures.Expansion of organoids was achieved by using DPM in combination with embedding organoids in Matrigel that was replaced with a defined thiol-hyaluronan triggered with PEGDA to form a hydrogel with a rheology[G*]of less than 100 Pa.The combination is called the BTSC-Expansion-Glycogel-System(BEX-gel system)for expanding BTSCs as a monolayer or as organoids.The BTSC organoids were expanded more than 3000-fold ex vivo in the BEX-gel system within 70 days while maintaining phenotypic traits indicative of stem/progenitors.Stem-cell-patch grafting of expanded BTSC organoids was performed on the livers of Fah-/-mice with tyrosinemia and resulted in the rescue of the mice and restoration of their normal liver functions.The BEX-gel system for BTSC organoid expansion provides a strategy to generate sufficient numbers of organoids for the therapeutic treatments of liver diseases.
基金National Key R&D Program of China(2022YFA1103200,2017YFA0106400,2021YFA1100900)Ministry of Science and Technology of China(2020YFC2002804)+3 种基金National Natural Science Foundation of China(91749124,81772389,82070108)Major Program of Development Fund for Shanghai Zhangjiang National Innovation Demonstration Zone(ZJ2018-ZD-004)Fundamental Research Funds for the Central Universities(22120190149 and kx0200020173386)Peak Disciplines(Type IV)of Institutions of Higher Learning in Shanghai。
文摘Fibroblast activation protein(Fap)is a serine protease that degrades denatured type I collagen,α2-antiplasmin and FGF21.Fap is highly expressed in bone marrow stromal cells and functions as an osteogenic suppressor and can be inhibited by the bone growth factor Osteolectin(Oln).Fap is also expressed in synovial fibroblasts and positively correlated with the severity of rheumatoid arthritis(RA).However,whether Fap plays a critical role in osteoarthritis(OA)remains poorly understood.Here,we found that Fap is significantly elevated in osteoarthritic synovium,while the genetic deletion or pharmacological inhibition of Fap significantly ameliorated posttraumatic OA in mice.Mechanistically,we found that Fap degrades denatured type II collagen(Col II)and Mmp13-cleaved native Col II.Intra-articular injection of r Fap significantly accelerated Col II degradation and OA progression.In contrast,Oln is expressed in the superficial layer of articular cartilage and is significantly downregulated in OA.Genetic deletion of Oln significantly exacerbated OA progression,which was partially rescued by Fap deletion or inhibition.Intra-articular injection of r Oln significantly ameliorated OA progression.Taken together,these findings identify Fap as a critical pathogenic factor in OA that could be targeted by both synthetic and endogenous inhibitors to ameliorate articular cartilage degradation.
基金supported by the Peak Disciplines(Type IV)of Institutions of Higher Learning in Shanghai,the Discipline Leader Program of Pudong New District Health and Family Planning Commission(No.PWRd2018-02)the Natural Science Foundation of Jiangxi Province(Nos.20181ACB20021 and 20181BAB205044),China.
文摘diabetes mellitus(DM)is a disease syndrome characterized by chronic hyperglycaemia.A long-term high-glucose environment leads to reactive oxygen species(ROS)production and nuclear DNA damage.human umbilical cord mesenchymal stem cell(HUcMSC)infusion induces significant antidiabetic effects in type 2 diabetes mellitus(T2DM)rats.Insulin-like growth factor 1(IGF1)receptor(IGF1R)is important in promoting glucose metabolism in diabetes;however,the mechanism by which HUcMSC can treat diabetes through IGF1R and DNA damage repair remains unclear.In this study,a DM rat model was induced with high-fat diet feeding and streptozotocin(STZ)administration and rats were infused four times with HUcMSC.Blood glucose,interleukin-6(IL-6),IL-10,glomerular basement membrane,and renal function were examined.Proteins that interacted with IGF1R were determined through coimmunoprecipitation assays.The expression of IGF1R,phosphorylated checkpoint kinase 2(p-CHK2),and phosphorylated protein 53(p-p53)was examined using immunohistochemistry(IHC)and western blot analysis.Enzyme-linked immunosorbent assay(ELISA)was used to determine the serum levels of 8-hydroxydeoxyguanosine(8-OHdG).Flow cytometry experiments were used to detect the surface markers of HUcMSC.The identification of the morphology and phenotype of HUcMSC was performed by way of oil red“O”staining and Alizarin red staining.DM rats exhibited abnormal blood glucose and IL-6/10 levels and renal function changes in the glomerular basement membrane,increased the expression of IGF1 and IGF1R.IGF1R interacted with CHK2,and the expression of p-CHK2 was significantly decreased in IGF1R-knockdown cells.When cisplatin was used to induce DNA damage,the expression of p-CHK2 was higher than that in the IGF1R-knockdown group without cisplatin treatment.HUcMSC infusion ameliorated abnormalities and preserved kidney structure and function in DM rats.The expression of IGF1,IGF1R,p-CHK2,and p-p53,and the level of 8-OHdG in the DM group increased significantly compared with those in the control group,and decreased after HUcMSC treatment.Our results suggested that IGF1R could interact with CHK2 and mediate DNA damage.HUcMSC infusion protected against kidney injury in DM rats.The underlying mechanisms may include HUcMSC-mediated enhancement of diabetes treatment via the IGF1R-CHK2-p53 signalling pathway.
基金supported by grants from the National Key R&D Program of China(2022YFA1103200)National Natural Science Foundation Projects of China(81822012,82061130222,81771043,92049201,82001070)+1 种基金Shanghai Academic Leader of Science and Technology Innovation Action Plan(20XD1424000)the Shanghai Experimental Animal Research Project of Science and Technology Innovation Action Plan(8191101676,201409006400)。
文摘In growing children,growth plate cartilage has limited self-repair ability upon fracture injury always leading to limb growth arrest.Interestingly,one type of fracture injuries within the growth plate achieve amazing self-healing,however,the mechanism is unclear.Using this type of fracture mouse model,we discovered the activation of Hedgehog(Hh)signaling in the injured growth plate,which could activate chondrocytes in growth plate and promote cartilage repair.
基金funded by Major Program of National Key Research and Development Project(Nos.2020YFA0112600 and 2019YFA0801502)National Natural Science Foundation of China(Nos.82173019,82270638,and 82203741)+8 种基金Shanghai Pujiang Program(No.21PJD059)the Project of Shanghai Science and Technology Commission(Nos.22ZR1451100,19140902900,and 22Y11908500),Program of Shanghai Academic/Technology Research Leader(No.20XD1434000)Peak Disciplines(Type Ⅳ)of Institutions of Higher Learning in Shanghai,Jiangxi Provincial Natural Science Foundation(No.20212ACB206033)Shanghai Engineering Research Center of Stem Cells Translational Medicine(No.20DZ2255100)funded by Vesta Therapeutics(Bethesda,MD),an NIH grant(HL051587)awarded to J.Piedrahita(NCSU,Raleigh,NC)funding from the UNC School of Medicine,the Fibrolamellar Carcinoma Foundation(Greenwich,CT)by multiple NIH Core and Center grants(5P41EB002025)Center for Gastrointestinal and Biliary Disease Biology(NIDDK Grant:P30 DK034987)the Lineberger Cancer Center grant(NCI grant#CA016086).
文摘The liver has a complex cellular composition and a remarkable regenerative capacity.The primary cell types in the liver are two parenchymal cell populations,hepatocytes and cholangiocytes,that perform most of the functions of the liver and that are helped through interactions with non-parenchymal cell types comprising stellate cells,endothelia and various hemopoietic cell populations.The regulation of the cells in the liver is mediated by an insoluble complex of proteins and carbohydrates,the extracellular matrix,working synergistically with soluble paracrine and systemic signals.In recent years,with the rapid development of genetic sequencing technologies,research on the liver’s cellular composition and its regulatory mechanisms during various conditions has been extensively explored.Meanwhile breakthroughs in strategies for cell transplantation are enabling a future in which there can be a rescue of patients with end-stage liver diseases,offering potential solutions to the chronic shortage of livers and alternatives to liver transplantation.This review will focus on the cellular mechanisms of liver homeostasis and how to select ideal sources of cells to be transplanted to achieve liver regeneration and repair.Recent advances are summarized for promoting the treatment of end-stage liver diseases by forms of cell transplantation that now include grafting strategies.
文摘Dear Editor,Myocardial infarction is one of the leading causes of morbidity and mortality.Stem/progenitor cells therapy has emerged as a promising strategy for the cardiac repair,especially those derived from cardiac tissue,have attracted worldwide attention(Tompkins et al.,2018).However,challenges and controversies remain in characterizing functional progenitors and explaining their mechanisms of action.
基金supported by Ministry of Science and Technology of China(Grants 2017YFC1104001,2017YFC1104002,2020YFC2002804)National Natural Science Foundation of China(Grants 31900980,31970970,31730030,81941011,31971279,31771053,82030035,31900749)+5 种基金Beijing Science and Technology Program(Grant Z181100001818007)Natural Science Foundation of Beijing Municipality(Grant KZ201810025030,7222004)Priority of Shanghai Key Discipline of Medicine(Grant 2017ZZ02020)Foundation of Shanghai Municipal Education Commission(Grant 2019-01-07-00-07-E00055)the Key R&D Program of Jiangsu(Grant BE2020026)Fundamental Research Funds for Central Public Welfare Research Institutes(Grant 2022CZ-12).
文摘Spinal cord injury(SCI)is a severe damage usually leading to limb dysesthesia,motor dysfunction,and other physiological disability.We have previously shown that NT3-chitosan could trigger an acute SCI repairment in rats and non-human primates.Due to the negative effect of inhibitory molecules in glial scar on axonal regeneration,however,the role of NT3-chitosan in the treatment of chronic SCI remains unclear.Compared with the fresh wound of acute SCI,how to handle the lesion core and glial scars is a major issue related to chronic-SCI repair.Here we report,in a chronic complete SCI rat model,establishment of magnetic resonancediffusion tensor imaging(MR-DTI)methods to monitor spatial and temporal changes of the lesion area,which matched well with anatomical analyses.Clearance of the lesion core via suction of cystic tissues and trimming of solid scar tissues before introducing NT3-chitosan using either a rigid tubular scaffold or a soft gel form led to robust neural regeneration,which interconnected the severed ascending and descending axons and accompanied with electrophysiological and motor functional recovery.In contrast,cystic tissue extraction without scar trimming followed by NT3-chitosan injection,resulted in little,if any regeneration.Taken together,after lesion core clearance,NT3-chitosan can be used to enable chronic-SCI repair and MR-DTI-based mapping of lesion area and monitoring of ongoing regeneration can potentially be implemented in clinical studies for subacute/chronic-SCI repair.
基金This study is supported by the National Key research and development program(2016YFA 0100801)the Natural Science Foundation of China(31930044,31725012,31620103904)+2 种基金the Foundation of Shanghai Municipal Education Commission(2019-01-07-00-07-E00062)the Collaborative Innovation Program of Shanghai Municipal Health Commission(2020CXJQ01)the Shanghai Municipal Science and Technology Major Project(No.2018SHZDZX01)and ZJ Lab to Y.-C.Y.
文摘Rett syndrome(RTT)is a progressive neurodevelop-mental disorder,mainly caused by mutations in MeCP2 and currently with no cure.We report here that neurons from R106W MeCP2 RTT human iPSCs as well as human embryonic stem cells after MeCP2 knockdown exhibit consistent and long-lasting impairment in maturation as indicated by impaired action potentials and passive membrane properties as well as reduced soma size and spine density.Moreover,RTT-inherent defects in neuronal maturation could be pan-neuronal and occurred in neurons with both dorsal and ventral forebrain features.Knockdown of MeCP2 led to more severe neuronal deficits as compared to RTT iPSC-derived neurons,which appeared to retain partial function.Strikingly,consistent deficits in nuclear size,dendritic complexity and circuitry-dependent spontaneous postsynaptic currents could only be observed in MeCP2 knockdown neurons but not RTT iPSC-derived neurons.Both neuron-intrinsic and circuitry-dependent deficits of MeCP2-deficient neurons could be fully or partially rescued by re-expression of wild type or T158M MeCP2,strengthening the dosage dependency of MeCP2 on disease phenotypes and also the partial function of the mutant.Our findings thus reveal stable neuronal maturation deficits and unexpectedly,graded sensitivities of neuron-inherent and neural transmission phenotypes towards the extent of MeCP2 deficiency,which is informative for future therapeutic development.
基金This work was supported by Key Research and Development Program,Ministry of Science and Technology of China(2017YFA0105601,2018YFA0800104)National Natural Science Foundation of China(31771613,32070823)Fundamental Research Funds for the Central Universities(22120200411).
文摘Ischemic heart disease is one of the main causes of morbidity and mortality in the world. In adult mammalianhearts, most cardiomyocytes are terminally differentiated and have extremely limited capacity of proliferation,making it impossible to regenerate the heart after injuries such as myocardial infarction. MicroRNAs (miRNAs), aclass of non-coding single-stranded RNA, which are involved in mRNA silencing and the regulation of posttranscriptionalgene expression, have been shown to play a crucial role in cardiac development and cardiomyocyteproliferation. Muscle specific miRNAs such as miR-1 are key regulators of cardiomyocyte maturation and growth,while miR-199-3p and other miRNAs display potent activity to induce proliferation of cardiomyocytes. Given theirsmall size and relative pleiotropic effects, miRNAs have gained significant attraction as promising therapeutic targetsor tools in cardiac regeneration. Increasing number of studies demonstrated that overexpression or inhibition ofspecific miRNAs could induce cardiomyocyte proliferation and cardiac regeneration. Some common targets of proproliferationmiRNAs, such as the Hippo-Yap signaling pathway, were identified in multiple species, highlighting thepower of miRNAs as probes to dissect core regulators of biological processes. A number of miRNAs have beenshown to improve heart function after myocardial infarction in mice, and one trial in swine also demonstratedpromising outcomes. However, technical difficulties, especially in delivery methods, and adverse effects, such asuncontrolled proliferation, remain. In this review, we summarize the recent progress in miRNA research in cardiacdevelopment and regeneration, examine the mechanisms of miRNA regulating cardiomyocyte proliferation, anddiscuss its potential as a new strategy for cardiac regeneration therapy.
基金This work was supported by grants from the National Key Research and Development Program of China(2018YFA0108000 and 2019YFA0110300)the National Natural Science Foundation of China(8205020,32000689,31400934,31771132,31872760,31801204,and 31800858)+3 种基金the Science and Technology Commission of Shanghai Municipality(19JC1415100 and 21140902300)the Shanghai Municipal Education Commission(C120114)China Postdoctoral Science Foundation(2017M621526)the Fundamental Research Funds for the Central Universities,and the Major Program of Development Fund for Shanghai Zhangjiang National Innovation Demonstration Zone(Stem Cell Strategic Biobank and Clinical Translation Platform of Stem Cell Technology,ZJ2018-ZD-004).
文摘Congenital hydrocephalus is a major neurological disorder with high rates of morbidity and mortality;however,the underlying cellular and molecular mechanisms remain largely unknown.Reproducible animal models mirroring both embryonic and postnatal hydrocephalus are also limited.Here,we describe a new mouse model of congenital hydrocephalus through knockout ofβ-catenin in Nkx2.1-expressing regional neural progenitors.Progressive ventriculomegaly and an enlarged brain were consistently observed in knockout mice from embryonic day 12.5 through to adulthood.Transcriptome profiling revealed severe dysfunctions in progenitor maintenance in the ventricular zone and therefore in cilium biogenesis afterβ-catenin knockout.Histological analyses also revealed an aberrant neuronal layout in both the ventral and dorsal telencephalon in hydrocephalic mice at both embryonic and postnatal stages.Thus,knockout ofβ-catenin in regional neural progenitors leads to congenital hydrocephalus and provides a reproducible animal model for studying pathological changes and developing therapeutic interventions for this devastating disease.
