The damage of human corneal cells encounter with the problem of availability of corneal cells for replacement. Limitation of the source of corneal cells has been realized. An attempt of development of corneal epitheli...The damage of human corneal cells encounter with the problem of availability of corneal cells for replacement. Limitation of the source of corneal cells has been realized. An attempt of development of corneal epithelial-like cells from the human skin-derived precursor (hSKPs) has been made in this study. Combination of three essential growth factors: epidermal growth factor (EGF), keratinocyte growth factor (KGF) and hepatocyte growth factor (HGF) could demonstrate successfully induction of hSKPs to differentiation into corneal cells. The induced cells expressed the appearance of markers of corneal epithelial cells as shown by the presence of keratin 3 (K3) by antibody label and Western blot assay. The K3 gene expression of induced hSKPs cells as shown by reverse transcription-polymerase chain reaction (RT-PCR) technology was also demonstrated. The presence of these markers at both gene and protein levels could lead to our conclusion that the directional transdifferentiation of hSKPs cells into corneal epithelial cells was successfully done under this cell induction protocol. The finding shows a newly available stem cell source can be obtained from easily available skin. Cells from autologous human skin might be used for corneal disorder treatment in future clinical application.展开更多
Pancreatic insulin-secreting β-cells are essential regulators of glucose metabolism. New strategies are cur-rently being investigated to create insulin-producing β cells to replace deficient β cells, including the ...Pancreatic insulin-secreting β-cells are essential regulators of glucose metabolism. New strategies are cur-rently being investigated to create insulin-producing β cells to replace deficient β cells, including the differentiation of either stem or progenitor cells, and the newly uncovered transdifferentiation of mature non-β islet cell types. However, in order to correctly drive any cell to adopt a new β-cell fate, a better understanding of the in vivo mechanisms involved in the plasticity and biology of islet cells is urgently required. Here, we review the recent studies reporting the phenomenon of transdifferentiation of α cells into β cells by focusing on the major candidates and contexts revealed to be involved in adult β-cell regeneration through this process. The possible underlying mechanisms of transdifferentiation and the interactions between several key factors involved in the process are also addressed. We propose that it is of importance to further study the molecular and cellular mechanisms underlying α- to β-cell transdifferentiation, in order to make β-cell regeneration from α cells a relevant and realizable strategy for developing cell-replacement therapy.展开更多
BACKGROUND Senescence is characterized by a decline in hepatocyte function,with impairment of metabolism and regenerative capacity.Several models that duplicate liver functions in vitro are essential tools for studyin...BACKGROUND Senescence is characterized by a decline in hepatocyte function,with impairment of metabolism and regenerative capacity.Several models that duplicate liver functions in vitro are essential tools for studying drug metabolism,liver diseases,and organ regeneration.The human HepaRG cell line represents an effective model for the study of liver metabolism and hepatic progenitors.However,the impact of senescence on HepaRG cells is not yet known.AIM To characterize the effects of senescence on the transdifferentiation capacity and mitochondrial metabolism of human HepaRG cells.METHODS We compared the transdifferentiation capacity of cells over 10(passage 10[P10])vs P20.Aging was evaluated by senescence-associated(SA)beta-galactosidase activity and the comet assay.HepaRG transdifferentiation was analyzed by confocal microscopy and flow cytometry(expression of cluster of differentiation 49a[CD49a],CD49f,CD184,epithelial cell adhesion molecule[EpCAM],and cytokeratin 19[CK19]),quantitative PCR analysis(expression of albumin,cytochrome P4503A4[CYP3A4],γ-glutamyl transpeptidase[γ-GT],and carcinoembryonic antigen[CEA]),and functional analyses(albumin secretion,CYP3A4,andγ-GT).Mitochondrial respiration and the ATP and nicotinamide adenine dinucleotide(NAD^(+))/NAD with hydrogen(NADH)content were also measured.RESULTS SAβ-galactosidase staining was higher in P20 than P10 HepaRG cells;in parallel,the comet assay showed consistent DNA damage in P20 HepaRG cells.With respect to P10,P20 HepaRG cells exhibited a reduction of CD49a,CD49f,CD184,EpCAM,and CK19 after the induction of transdifferentiation.Furthermore,lower gene expression of albumin,CYP3A4,andγ-GT,as well as reduced albumin secretion capacity,CYP3A4,andγ-GT activity were reported in transdifferentiated P20 compared to P10 cells.By contrast,the gene expression level of CEA was not reduced by transdifferentiation in P20 cells.Of note,both cellular and mitochondrial oxygen consumption was lower in P20 than in P10 transdifferentiated cells.Finally,both ATP and NAD^(+)/NADH were depleted in P20 cells with respect to P10 cells.CONCLUSION SA mitochondrial dysfunction may limit the transdifferentiation potential of HepaRG cells,with consequent impairment of metabolic and regenerative properties,which may alter applications in basic studies.展开更多
Background:Myogenic transdifferentiation can be accomplished through ectopic MYOD1 expression,which is facilitated by various signaling pathways associated with myogenesis.In this study,we attempted to transdifferenti...Background:Myogenic transdifferentiation can be accomplished through ectopic MYOD1 expression,which is facilitated by various signaling pathways associated with myogenesis.In this study,we attempted to transdifferentiate pig embryonic fibroblasts(PEFs)myogenically into skeletal muscle through overexpression of the pig MYOD1 gene and modulation of the FGF,TGF-β,WNT,and cAMP signaling pathways.Results:The MYOD1 overexpression vector was constructed based on comparative sequence analysis,demonstrating that pig MYOD1 has evolutionarily conserved domains across various species.Although forced MYOD1 expression through these vectors triggered the expression of endogenous muscle markers,transdifferentiated muscle cells from fibroblasts were not observed.Therefore,various signaling molecules,including FGF2,SB431542,CHIR99021,and forskolin,along with MYOD1 overexpression were applied to enhance the myogenic reprogramming.The modified conditions led to the derivation of myotubes and activation of muscle markers in PEFs,as determined by qPCR and immunostaining.Notably,a sarcomere-like structure was observed,indicating that terminally differentiated skeletal muscle could be obtained from transdifferentiated cells.Conclusions:In summary,we established a protocol for reprogramming MYOD1-overexpressing PEFs into the mature skeletal muscle using signaling molecules.Our myogenic reprogramming can be used as a cell source for muscle disease models in regenerative medicine and the production of cultured meat in cellular agriculture.展开更多
Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured...Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured.A transdifferentiation model of primary rat lung fibroblasts was induced by free silica.Levels ofα-SMA protein,IGF-IIR protein and mRNA were measured by immunocytochemistry,Western blot and RT-PCR,respectively.Lung fibroblasts were treated with Wortmannin.Results The expression levels ofα-SMA and IGF-IIR increased with the increasing free silica concentration and decreased after Wortmannin was used.Conclusion The IGF-IIR plays an important role in free silica-induced transdifferentiation of primary rat lung fibroblasts.展开更多
To investigate the role of connective tissue growth factor (CTGF) in transdifferentiation of human renal tubular epithelial cell (HKC), in vitro cultured HKC cells were divided into 3 groups: negtive control, low dose...To investigate the role of connective tissue growth factor (CTGF) in transdifferentiation of human renal tubular epithelial cell (HKC), in vitro cultured HKC cells were divided into 3 groups: negtive control, low dose CTGF-treated group (rh CTGF, 2.5 ng/ml) and high dose CTGF-treated (rhCTGF, 5.0 ng/ml). Then the expression of α-smooth muscle actin (α-SMA) were assessed by indirect immuno-fluorescence, and the percentage of α-SMA positive cells were assessed by flow cytometry. RT-PCR were also performed to examine the mRNA level of α-SMA. Upon the stimulation of different concentrations of rhCTGF, the expression of α-SMA were markedly stronger than that in negative controls. The percentages of α-SMA positive cells were significantly higher in the stimulated groups than that of negative controls (38.9 %, 65.5 % vs 2.4 %, P<0.01) .α-SMA mRNA levels were also up-regulated by the stimulation of rhCTGF (P<0.01). These results suggest that CTGF can promote the transdifferentiation of human renal tubular epithelial cells towards myofibroblast (Myo-F).展开更多
Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s di...Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s disease are characte rized by significant neuronal loss.Unfo rtunately,the neurons of most mammals including humans do not possess the ability to self-regenerate.Replenishment of lost neurons becomes an appealing therapeutic strategy to reve rse the disease phenotype.Transplantation of pluripotent neural stem cells can supplement the missing neurons in the brain,but it carries the risk of causing gene mutation,tumorigenesis,severe inflammation,and obstructive hydrocephalus induced by brain edema.Conversion of neural or non-neural lineage cells into functional neurons is a promising strategy for the diseases involving neuron loss,which may overcome the above-mentioned disadvantages of neural stem cell therapy.Thus far,many strategies to transfo rm astrocytes,fibroblasts,microglia,Muller glia,NG2 cells,and other glial cells to mature and functional neurons,or for the conversion between neuronal subtypes have been developed thro ugh the regulation of transcription factors,polypyrimidine tra ct binding protein 1(PTBP1),and small chemical molecules or are based on a combination of several factors and the location in the central nervous system.However,some recent papers did not obtain expected results,and discrepancies exist.Therefore,in this review,we discuss the history of neuronal transdifferentiation,summarize the strategies for neuronal replenishment and conversion from glia,especially astrocytes,and point out that biosafety,new strategies,and the accurate origin of the truly co nverted neurons in vivo should be focused upon in future studies.It also arises the attention of replenishing the lost neurons from glia by gene therapies such as up-regulation of some transc ription factors or downregulation of PTBP1 or drug interfe rence therapies.展开更多
In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been sho...In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been shown to reprogram astrocytes to functional neurons in situ. In this study, we used AAV-PHP.e B-GFAP-sh PTB to knockdown PTB in a mouse model of ischemic stroke induced by endothelin-1, and investigated the effects of GFAP-sh PTB-mediated direct reprogramming to neurons. Our results showed that in the mouse model of ischemic stroke, PTB knockdown effectively reprogrammed GFAP-positive cells to neurons in ischemic foci, restored neural tissue structure, reduced inflammatory response, and improved behavioral function. These findings validate the effectiveness of in situ transdifferentiation of astrocytes, and suggest that the approach may be a promising strategy for stroke treatment.展开更多
Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional ce...Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional cellular paradigm.However,the mechanisms appear much more complicated than we thought since a bulk of studies on efferocytosis,transdifferentiation and novel cell death forms such as ferroptosis,pyroptosis,and extracellular trap were reported.Discovery of novel pathological cellular landscapes provides a large number of therapeutic targets.On the other side,the unsatisfactory therapeutic effects of current treatment with lipid-lowering drugs as the cornerstone also restricts the efforts to reduce global AS burden.Stem cell-or nanoparticle-based strategies spurred a lot of attention due to the attractive therapeutic effects and minimized adverse effects.Given the complexity of pathological changes of AS,attempts to develop an almighty medicine based on single mechanisms could be theoretically challenging.In this review,the top stories in the cellular landscapes during the initiation and progression of AS and the therapies were summarized in an integrated perspective to facilitate efforts to develop a multi-targets strategy and fill the gap between mechanism research and clinical translation.The future challenges and improvements were also discussed.展开更多
Objective: To observe the imbalance of anatomical and functional innervation factors of sympathetic nerves, nerve growth factor(NGF) and leukemia inhibitory factor(LIF), in salt-sensitive hypertensive heart failure ra...Objective: To observe the imbalance of anatomical and functional innervation factors of sympathetic nerves, nerve growth factor(NGF) and leukemia inhibitory factor(LIF), in salt-sensitive hypertensive heart failure rats and to explore the effects of treatment with Guizhi Decoction(桂枝汤) on sympathetic remodeling by inhibiting cholinergic transdifferentiation. Methods: SS-13 BN and Dahl salt-sensitive(DS) rats were divided into 3 groups: SS-13 BN group(control group, n=9), DS group(model group, n=9) and GS group(Guizhi Decoction, n=9). After 10 weeks of a high-salt diet, the GS group rats were given Guizhi Decoction and other two groups were given saline at an equal volume as a vehicle. After 4 weeks’ intragastric administration, rats were executed to detect the relevant indicators. Echocardiography and plasma n-terminal pro-B type natriuretic peptide(NT-proBNP) levels were used to assess cardiac function. Noradrenaline(NA) levels in the plasma and myocardium were detected to evaluate the sympathetic function. NGF and LIF expression were detected in the myocardium by Western blot or quantitative real-time PCR. Double immunofluorescence or Western blot was used to detect tyrosine hydroxylase(TH), choline acetyltransferase(CHAT) and growth associated protein 43(GAP43) in order to reflect anatomical and functional changes of sympathetic nerves. Results: DS group had anatomical and functional deterioration of sympathetic nerves in the decompensation period of heart failure compared with SS-13 BN group. Compared with the DS group, Guizhi Decoction significantly decreased the expression of LIF mRNA/protein(P<0.01), increased the expression of NGF(P<0.05 or P<0.01), enhanced the levels of TH^+/GAP43^+ and TH^+/CHAT^+ positive nerve fibers(P<0.01), and improved the protein expression of TH and GAP43 in left ventricle, but had no effect on CHAT(P>0.05). Guizhi Decoction inhibited inflammatory infiltration and collagen deposition of myocardial injury, increased the content of myocardial NA(P<0.05), reduced the plasma NA level(P<0.01), improved cardiac function(P<0.01), and improved weight and blood pressure to some extent(P<0.05), compared with DS group. Conclusions: Guizhi Decoction could inhibit cholinergic transdifferentiation of sympathetic nerves, improve the anatomical and functional denervation of sympathetic nerves, and delay the progression of decompensated heart failure. The mechanism may be associated with the correction of the imbalance of NGF and LIF.展开更多
Objective: The effects of hydraulic pressure on renal tubular epithelial-myofibroblast transdifferentiation (TEMT) were investigated. Methods: We applied hydraulic pressure (50 cmH2O) to normal rat kidney tubular epit...Objective: The effects of hydraulic pressure on renal tubular epithelial-myofibroblast transdifferentiation (TEMT) were investigated. Methods: We applied hydraulic pressure (50 cmH2O) to normal rat kidney tubular epithelial cells (NRK52E) for different durations. Furthermore, different pressure magnitudes were applied to cells. The morphology, cytoskeleton, and expression of myofibroblastic marker protein and transforming growth factor-β1 (TGF-β1) of NRK52E cells were examined. Results: Disorganized actin filaments and formation of curling clusters in actin were seen in the cytoplasm of pressurized cells. We verified that de novo expression of α-smooth muscle actin induced by pressure, which indicated TEMT, was dependent on both the magnitude and duration of pressure. TGF-β1 expression was significantly upregulated under certain conditions, which implies that the induction of TEMT by hydraulic pressure is related with TGF-β1. Conclusion: We illustrate for the first time that hydraulic pressure can induce TEMT in a pressure magnitude- and duration-dependent manner, and that this TEMT is accompanied by TGF-β1 secretion.展开更多
Microglia, the main driver of neuroinflammation, play a central role in the initiation and exacerbation of various neurodegenerative diseases and are now considered a promising therapeutic target. Previous studies on ...Microglia, the main driver of neuroinflammation, play a central role in the initiation and exacerbation of various neurodegenerative diseases and are now considered a promising therapeutic target. Previous studies on in vitro human microglia and in vivo rodent models lacked scalability, consistency, or physiological relevance, which deterred successful therapeutic outcomes for the past decade. Here we review human blood monocyte-derived microglia-like cells as a robust and consistent approach to generate a patient-specific microglia-like model that can be used in extensive cohort studies for drug testing. We will highlight the strength and applicability of human blood monocyte-derived microglia-like cells to increase translational outcomes by reviewing the advantages of human blood monocyte-derived microglia-like cells in addressing patient heterogeneity and stratification, the basis of personalized medicine.展开更多
基金Supported by Stem Cell Project,National Research Council of Thailand (NRCT),Cell Engineering and Tissue Growth, Institute of Molecular Biosciences and Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Thailand
文摘The damage of human corneal cells encounter with the problem of availability of corneal cells for replacement. Limitation of the source of corneal cells has been realized. An attempt of development of corneal epithelial-like cells from the human skin-derived precursor (hSKPs) has been made in this study. Combination of three essential growth factors: epidermal growth factor (EGF), keratinocyte growth factor (KGF) and hepatocyte growth factor (HGF) could demonstrate successfully induction of hSKPs to differentiation into corneal cells. The induced cells expressed the appearance of markers of corneal epithelial cells as shown by the presence of keratin 3 (K3) by antibody label and Western blot assay. The K3 gene expression of induced hSKPs cells as shown by reverse transcription-polymerase chain reaction (RT-PCR) technology was also demonstrated. The presence of these markers at both gene and protein levels could lead to our conclusion that the directional transdifferentiation of hSKPs cells into corneal epithelial cells was successfully done under this cell induction protocol. The finding shows a newly available stem cell source can be obtained from easily available skin. Cells from autologous human skin might be used for corneal disorder treatment in future clinical application.
基金Supported by The Agence National de Recherche(ANR 2010 BLAN 1240 01)the Ligue contre le Cancer du Rh ne and de la Loire+3 种基金the CMIRA program of Region Rh?ne-Alpes,No.12004959-01the Fondation ARC pour la Recherche sur le Cancer,France,No.SFI20101201530National Nature Science Foundation of China,No.NSFC81170719,No.81370960Shanghai New Excellent Youth Program,No.XYQ2011009
文摘Pancreatic insulin-secreting β-cells are essential regulators of glucose metabolism. New strategies are cur-rently being investigated to create insulin-producing β cells to replace deficient β cells, including the differentiation of either stem or progenitor cells, and the newly uncovered transdifferentiation of mature non-β islet cell types. However, in order to correctly drive any cell to adopt a new β-cell fate, a better understanding of the in vivo mechanisms involved in the plasticity and biology of islet cells is urgently required. Here, we review the recent studies reporting the phenomenon of transdifferentiation of α cells into β cells by focusing on the major candidates and contexts revealed to be involved in adult β-cell regeneration through this process. The possible underlying mechanisms of transdifferentiation and the interactions between several key factors involved in the process are also addressed. We propose that it is of importance to further study the molecular and cellular mechanisms underlying α- to β-cell transdifferentiation, in order to make β-cell regeneration from α cells a relevant and realizable strategy for developing cell-replacement therapy.
文摘BACKGROUND Senescence is characterized by a decline in hepatocyte function,with impairment of metabolism and regenerative capacity.Several models that duplicate liver functions in vitro are essential tools for studying drug metabolism,liver diseases,and organ regeneration.The human HepaRG cell line represents an effective model for the study of liver metabolism and hepatic progenitors.However,the impact of senescence on HepaRG cells is not yet known.AIM To characterize the effects of senescence on the transdifferentiation capacity and mitochondrial metabolism of human HepaRG cells.METHODS We compared the transdifferentiation capacity of cells over 10(passage 10[P10])vs P20.Aging was evaluated by senescence-associated(SA)beta-galactosidase activity and the comet assay.HepaRG transdifferentiation was analyzed by confocal microscopy and flow cytometry(expression of cluster of differentiation 49a[CD49a],CD49f,CD184,epithelial cell adhesion molecule[EpCAM],and cytokeratin 19[CK19]),quantitative PCR analysis(expression of albumin,cytochrome P4503A4[CYP3A4],γ-glutamyl transpeptidase[γ-GT],and carcinoembryonic antigen[CEA]),and functional analyses(albumin secretion,CYP3A4,andγ-GT).Mitochondrial respiration and the ATP and nicotinamide adenine dinucleotide(NAD^(+))/NAD with hydrogen(NADH)content were also measured.RESULTS SAβ-galactosidase staining was higher in P20 than P10 HepaRG cells;in parallel,the comet assay showed consistent DNA damage in P20 HepaRG cells.With respect to P10,P20 HepaRG cells exhibited a reduction of CD49a,CD49f,CD184,EpCAM,and CK19 after the induction of transdifferentiation.Furthermore,lower gene expression of albumin,CYP3A4,andγ-GT,as well as reduced albumin secretion capacity,CYP3A4,andγ-GT activity were reported in transdifferentiated P20 compared to P10 cells.By contrast,the gene expression level of CEA was not reduced by transdifferentiation in P20 cells.Of note,both cellular and mitochondrial oxygen consumption was lower in P20 than in P10 transdifferentiated cells.Finally,both ATP and NAD^(+)/NADH were depleted in P20 cells with respect to P10 cells.CONCLUSION SA mitochondrial dysfunction may limit the transdifferentiation potential of HepaRG cells,with consequent impairment of metabolic and regenerative properties,which may alter applications in basic studies.
基金supported by the BK21 Four program,the Korea Evaluation Institute of Industrial Technology(KEIT,20012411)the National Research Foundation of Korea(NRF)grant(2021R1A2C4001837).
文摘Background:Myogenic transdifferentiation can be accomplished through ectopic MYOD1 expression,which is facilitated by various signaling pathways associated with myogenesis.In this study,we attempted to transdifferentiate pig embryonic fibroblasts(PEFs)myogenically into skeletal muscle through overexpression of the pig MYOD1 gene and modulation of the FGF,TGF-β,WNT,and cAMP signaling pathways.Results:The MYOD1 overexpression vector was constructed based on comparative sequence analysis,demonstrating that pig MYOD1 has evolutionarily conserved domains across various species.Although forced MYOD1 expression through these vectors triggered the expression of endogenous muscle markers,transdifferentiated muscle cells from fibroblasts were not observed.Therefore,various signaling molecules,including FGF2,SB431542,CHIR99021,and forskolin,along with MYOD1 overexpression were applied to enhance the myogenic reprogramming.The modified conditions led to the derivation of myotubes and activation of muscle markers in PEFs,as determined by qPCR and immunostaining.Notably,a sarcomere-like structure was observed,indicating that terminally differentiated skeletal muscle could be obtained from transdifferentiated cells.Conclusions:In summary,we established a protocol for reprogramming MYOD1-overexpressing PEFs into the mature skeletal muscle using signaling molecules.Our myogenic reprogramming can be used as a cell source for muscle disease models in regenerative medicine and the production of cultured meat in cellular agriculture.
基金supported by the Research Fund from theNational Natural Science Foundation of China(#81102109)
文摘Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured.A transdifferentiation model of primary rat lung fibroblasts was induced by free silica.Levels ofα-SMA protein,IGF-IIR protein and mRNA were measured by immunocytochemistry,Western blot and RT-PCR,respectively.Lung fibroblasts were treated with Wortmannin.Results The expression levels ofα-SMA and IGF-IIR increased with the increasing free silica concentration and decreased after Wortmannin was used.Conclusion The IGF-IIR plays an important role in free silica-induced transdifferentiation of primary rat lung fibroblasts.
基金ThisworkwassupportedbyagrantfromtheScience&TechnologyFoundationofHubeiProvince (No .2 0 0 3AA30 1C14 )
文摘To investigate the role of connective tissue growth factor (CTGF) in transdifferentiation of human renal tubular epithelial cell (HKC), in vitro cultured HKC cells were divided into 3 groups: negtive control, low dose CTGF-treated group (rh CTGF, 2.5 ng/ml) and high dose CTGF-treated (rhCTGF, 5.0 ng/ml). Then the expression of α-smooth muscle actin (α-SMA) were assessed by indirect immuno-fluorescence, and the percentage of α-SMA positive cells were assessed by flow cytometry. RT-PCR were also performed to examine the mRNA level of α-SMA. Upon the stimulation of different concentrations of rhCTGF, the expression of α-SMA were markedly stronger than that in negative controls. The percentages of α-SMA positive cells were significantly higher in the stimulated groups than that of negative controls (38.9 %, 65.5 % vs 2.4 %, P<0.01) .α-SMA mRNA levels were also up-regulated by the stimulation of rhCTGF (P<0.01). These results suggest that CTGF can promote the transdifferentiation of human renal tubular epithelial cells towards myofibroblast (Myo-F).
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDB39050600(to RL)the National Natural Science Foundation of China,No.81971610(to RL)Beijing Rehabilitation Hospital Introduction of Talent Research Start-up Fund,No.2021R-008(to JZ)。
文摘Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s disease are characte rized by significant neuronal loss.Unfo rtunately,the neurons of most mammals including humans do not possess the ability to self-regenerate.Replenishment of lost neurons becomes an appealing therapeutic strategy to reve rse the disease phenotype.Transplantation of pluripotent neural stem cells can supplement the missing neurons in the brain,but it carries the risk of causing gene mutation,tumorigenesis,severe inflammation,and obstructive hydrocephalus induced by brain edema.Conversion of neural or non-neural lineage cells into functional neurons is a promising strategy for the diseases involving neuron loss,which may overcome the above-mentioned disadvantages of neural stem cell therapy.Thus far,many strategies to transfo rm astrocytes,fibroblasts,microglia,Muller glia,NG2 cells,and other glial cells to mature and functional neurons,or for the conversion between neuronal subtypes have been developed thro ugh the regulation of transcription factors,polypyrimidine tra ct binding protein 1(PTBP1),and small chemical molecules or are based on a combination of several factors and the location in the central nervous system.However,some recent papers did not obtain expected results,and discrepancies exist.Therefore,in this review,we discuss the history of neuronal transdifferentiation,summarize the strategies for neuronal replenishment and conversion from glia,especially astrocytes,and point out that biosafety,new strategies,and the accurate origin of the truly co nverted neurons in vivo should be focused upon in future studies.It also arises the attention of replenishing the lost neurons from glia by gene therapies such as up-regulation of some transc ription factors or downregulation of PTBP1 or drug interfe rence therapies.
基金supported by the National Natural Science Foundation of China,No.82071418the Natural Science Foundation of Fujian Province,No.2020J01612 (both to EH)。
文摘In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been shown to reprogram astrocytes to functional neurons in situ. In this study, we used AAV-PHP.e B-GFAP-sh PTB to knockdown PTB in a mouse model of ischemic stroke induced by endothelin-1, and investigated the effects of GFAP-sh PTB-mediated direct reprogramming to neurons. Our results showed that in the mouse model of ischemic stroke, PTB knockdown effectively reprogrammed GFAP-positive cells to neurons in ischemic foci, restored neural tissue structure, reduced inflammatory response, and improved behavioral function. These findings validate the effectiveness of in situ transdifferentiation of astrocytes, and suggest that the approach may be a promising strategy for stroke treatment.
基金supported by the National Natural Science Foundation of China(No.81573957,No.81874461 and No.82070307).
文摘Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional cellular paradigm.However,the mechanisms appear much more complicated than we thought since a bulk of studies on efferocytosis,transdifferentiation and novel cell death forms such as ferroptosis,pyroptosis,and extracellular trap were reported.Discovery of novel pathological cellular landscapes provides a large number of therapeutic targets.On the other side,the unsatisfactory therapeutic effects of current treatment with lipid-lowering drugs as the cornerstone also restricts the efforts to reduce global AS burden.Stem cell-or nanoparticle-based strategies spurred a lot of attention due to the attractive therapeutic effects and minimized adverse effects.Given the complexity of pathological changes of AS,attempts to develop an almighty medicine based on single mechanisms could be theoretically challenging.In this review,the top stories in the cellular landscapes during the initiation and progression of AS and the therapies were summarized in an integrated perspective to facilitate efforts to develop a multi-targets strategy and fill the gap between mechanism research and clinical translation.The future challenges and improvements were also discussed.
基金Supported by the National Natural Science Foundation of China(No.81673970)
文摘Objective: To observe the imbalance of anatomical and functional innervation factors of sympathetic nerves, nerve growth factor(NGF) and leukemia inhibitory factor(LIF), in salt-sensitive hypertensive heart failure rats and to explore the effects of treatment with Guizhi Decoction(桂枝汤) on sympathetic remodeling by inhibiting cholinergic transdifferentiation. Methods: SS-13 BN and Dahl salt-sensitive(DS) rats were divided into 3 groups: SS-13 BN group(control group, n=9), DS group(model group, n=9) and GS group(Guizhi Decoction, n=9). After 10 weeks of a high-salt diet, the GS group rats were given Guizhi Decoction and other two groups were given saline at an equal volume as a vehicle. After 4 weeks’ intragastric administration, rats were executed to detect the relevant indicators. Echocardiography and plasma n-terminal pro-B type natriuretic peptide(NT-proBNP) levels were used to assess cardiac function. Noradrenaline(NA) levels in the plasma and myocardium were detected to evaluate the sympathetic function. NGF and LIF expression were detected in the myocardium by Western blot or quantitative real-time PCR. Double immunofluorescence or Western blot was used to detect tyrosine hydroxylase(TH), choline acetyltransferase(CHAT) and growth associated protein 43(GAP43) in order to reflect anatomical and functional changes of sympathetic nerves. Results: DS group had anatomical and functional deterioration of sympathetic nerves in the decompensation period of heart failure compared with SS-13 BN group. Compared with the DS group, Guizhi Decoction significantly decreased the expression of LIF mRNA/protein(P<0.01), increased the expression of NGF(P<0.05 or P<0.01), enhanced the levels of TH^+/GAP43^+ and TH^+/CHAT^+ positive nerve fibers(P<0.01), and improved the protein expression of TH and GAP43 in left ventricle, but had no effect on CHAT(P>0.05). Guizhi Decoction inhibited inflammatory infiltration and collagen deposition of myocardial injury, increased the content of myocardial NA(P<0.05), reduced the plasma NA level(P<0.01), improved cardiac function(P<0.01), and improved weight and blood pressure to some extent(P<0.05), compared with DS group. Conclusions: Guizhi Decoction could inhibit cholinergic transdifferentiation of sympathetic nerves, improve the anatomical and functional denervation of sympathetic nerves, and delay the progression of decompensated heart failure. The mechanism may be associated with the correction of the imbalance of NGF and LIF.
基金This research was supported by the grants from the National Natural Science Foundation of China，the Science and Technology Research Projects of Sichuan Province
基金Project (No. 2007CB947802) supported by National Basic Research Program of China
文摘Objective: The effects of hydraulic pressure on renal tubular epithelial-myofibroblast transdifferentiation (TEMT) were investigated. Methods: We applied hydraulic pressure (50 cmH2O) to normal rat kidney tubular epithelial cells (NRK52E) for different durations. Furthermore, different pressure magnitudes were applied to cells. The morphology, cytoskeleton, and expression of myofibroblastic marker protein and transforming growth factor-β1 (TGF-β1) of NRK52E cells were examined. Results: Disorganized actin filaments and formation of curling clusters in actin were seen in the cytoplasm of pressurized cells. We verified that de novo expression of α-smooth muscle actin induced by pressure, which indicated TEMT, was dependent on both the magnitude and duration of pressure. TGF-β1 expression was significantly upregulated under certain conditions, which implies that the induction of TEMT by hydraulic pressure is related with TGF-β1. Conclusion: We illustrate for the first time that hydraulic pressure can induce TEMT in a pressure magnitude- and duration-dependent manner, and that this TEMT is accompanied by TGF-β1 secretion.
基金supported by grants from NHMRC (APP1125796)The Col Bambrick Memorial MND Research Grant+2 种基金The NTI MND Research Grantthe FightMND Foundationsupported by an NHMRC Senior Research Fellowship APP1118452。
文摘Microglia, the main driver of neuroinflammation, play a central role in the initiation and exacerbation of various neurodegenerative diseases and are now considered a promising therapeutic target. Previous studies on in vitro human microglia and in vivo rodent models lacked scalability, consistency, or physiological relevance, which deterred successful therapeutic outcomes for the past decade. Here we review human blood monocyte-derived microglia-like cells as a robust and consistent approach to generate a patient-specific microglia-like model that can be used in extensive cohort studies for drug testing. We will highlight the strength and applicability of human blood monocyte-derived microglia-like cells to increase translational outcomes by reviewing the advantages of human blood monocyte-derived microglia-like cells in addressing patient heterogeneity and stratification, the basis of personalized medicine.
