Bckground Stem cells, which have the ability to differentiate into insulin-producing cells （IPCs）, would provide a potentially unlimited source of islet cells for transplantation and alleviate the major limitations ...Bckground Stem cells, which have the ability to differentiate into insulin-producing cells （IPCs）, would provide a potentially unlimited source of islet cells for transplantation and alleviate the major limitations of availability and allogeneic rejection. Therefore, the utilization of stem cells is becoming the most promising therapy for diabetes mellitus （DM）. Here, we studied the differentiation capacity of the diabetic patient＇s bone marrow-derived mesenchymal stem cells （MSCs） and tested the feasibility of using MSCs for β-cell replacement. Methods Bone marrow-derived MSCs were obtained from 10 DM patients （5 type 1 DM and 5 type 2 DM） and induced to IPCs under a three-stage protocol. Representative cell surface antigen expression profiles of MSCs were analysed by flow cytometric analysis. Reverse transcription-polymerase chain reaction （RT-PCR） was performed to detect multiple genes related to pancreatic β-cell development and function. The identity of the IPCs was illustrated by the analysis of morphology, ditizone staining and immunocytochemistry. Release of insulin by these cells was confirmed by immunoradioassay. Results Flow cytometric analysis of MSCs at passage 3 showed that these cells expressed high levels of CD29 （98.28%）, CD44 （99.56%） and CD106 （98.34%）. Typical islet-like cell clusters were observed at the end of the protocol （18 days）. Ditizone staining and immunohistochemistry for insulin were both positive. These differentiated cells at stage 2 （10 days） expressed nestin, pancreatic duodenal homeobox-1 （PDX-1）, Neurogenin3, Pax4, insulin, glucagon, but at stage 3 （18 days） we observed the high expression of PDX-1, insulin, glucagon. Insulin was secreted by these cells in response to different concentrations of glucose stimulation in a regulated manner （P〈0.05）. Conclusions Bone marrow-derived MSCs from DM patients can differentiate into functional IPCs under certain conditions in vitro. Using diabetic patient＇s own bone marrow-deriv展开更多
AIM： To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells （ADSC） and bone marrow-derived mesenchymal stem cells （BMSC） in vitro. Transdifferentiation of BMSC into h...AIM： To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells （ADSC） and bone marrow-derived mesenchymal stem cells （BMSC） in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS： BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically analysed.RESULTS： BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors （C/EBPβ and HNF4α）, as demonstrated by adenoviral expression vectors.CONCLUSION： Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.展开更多
Barrett's esophagus is a premalignant condition caused by gastroesophageal reflux. Once developed, it can progress through varying grades of dysplasia to esoph-ageal adenocarcinoma. Whilst it is well accepted that...Barrett's esophagus is a premalignant condition caused by gastroesophageal reflux. Once developed, it can progress through varying grades of dysplasia to esoph-ageal adenocarcinoma. Whilst it is well accepted that Barrett's esophagus is caused by gastroesophageal reflux, the molecular mechanisms of its pathogenesis and progression to cancer remain unclear. MicroRNAs (miRNAs) are short segments of RNA that have been shown to control the expression of many human genes. They have been implicated in most cellular processes, and the role of miRNAs in disease development is be-coming increasingly evident. Understanding altered miRNA expression is likely to help unravel the molecular mechanisms that underpin the development of Barrett's esophagus and its progression to cancer.展开更多
The programmed cell death-1(PD-1)/PD-ligand 1(PD-L1)pathway is critical for normal pregnancy by promoting regulatory T(Treg)cell development and inhibiting the Th17 response.However,the relationship between the PD-1/P...The programmed cell death-1(PD-1)/PD-ligand 1(PD-L1)pathway is critical for normal pregnancy by promoting regulatory T(Treg)cell development and inhibiting the Th17 response.However,the relationship between the PD-1/PD-L1 pathway and the Treg/Th17 imbalance in pre-eclampsia(PE)is an enigma.In this study,decreased PD-1 and PD-L1 expression and a Treg/Th17 imbalance were observed at the maternal-fetal interface in PE.The regulatory effects of the PD-1/PD-L1 pathway on the Treg and Th17 cell quantities were determined in vitro by targeting T-cell proliferation,differentiation and transdifferentiation.First,decreased PD-1 expression might contribute to a higher Th17 cell frequency by promoting proliferation in PE.Second,the percentages of Treg but not Th17 cells differentiated from peripheral naive CD4+T cells were increased by PD-L1 Fc administration.This effect was accompanied by decreased PI3K/AKT/m-TOR and increased PTEN mRNA expression and was completely reversed by PD-1 blockade.Finally,the percentage of IL-17-producing Treg cells increased and was positively associated with the Th17 cell frequency in PE.Increased RORγt and IL-17 but not Foxp3 and IL-10 mRNA expression by Treg cells was observed with PD-1 blockade.Similar findings occurred when Treg cells were exposed to IL-6/IL-23/IL-1βand were reversed by PD-L1 Fc.Taken together,our findings indicate that the PD-1/PD-L1 pathway contributes to the Treg/Th17 imbalance via‘one-two punch’approaches:(i)promoting Th17 cell proliferation,(ii)inhibiting Treg cell differentiation and(iii)enhancing Treg cell plasticity into Th17 cells in PE.The therapeutic value of PD-L1 Fc for PE treatment will be explored in the future.展开更多
Liver fibrosis is a wound-healing response to chronic injuries, characterized by the excessive accumulation of extracellular matrix or scar tissue within the liver;in addition, its formation is associated with multipl...Liver fibrosis is a wound-healing response to chronic injuries, characterized by the excessive accumulation of extracellular matrix or scar tissue within the liver;in addition, its formation is associated with multiple cytokines as well as several cell types and a variety of signaling pathways. When liver fibrosis is not well controlled, it can progress to liver cirrhosis, but it is reversible in principle. Thus far, no efficient therapy is available for treatment of liver fibrosis. Although liver transplantation is the preferred strategy, there are many challenges remaining in this approach, such as shortage of donor organs, immunological rejection, and surgical complications. Hence, there is a great need for an alternative therapeutic strategy. Currently, mesenchymal stem cell (MSC) therapy is considered a promising therapeutic strategy for the treatment of liver fibrosis;advantageously, the characteristics of MSCs are continuous self-renewal, proliferation, multipotent differentiation, and immunomodulatory activities. The human umbilical cord-derived (hUC)-MSCs possess not only the common attributes of MSCs but also more stable biological characteristics, relatively easy accessibility, abundant source, and no ethical issues (e.g., bone marrow being the adult source), making hUC-MSCs a good choice for treatment of liver fibrosis. In this review, we summarize the biological characteristics of hUC-MSCs and their paracrine effects, exerted by secretion of various cytokines, which ultimately promote liver repair through several signaling pathways. Additionally, we discuss the capacity of hUC-MSCs to differentiate into hepatocyte-like cells for compensating the function of existing hepatocytes, which may aid in amelioration of liver fibrosis. Finally, we discuss the current status of the research field and its future prospects.展开更多
Background Tubulointerstitial renal fibrosis is the common end point of progressive kidney diseases, and tubular epithelial-myofibroblast transdifferentiation （TEMT） plays a key role in the progress of tubulointerst...Background Tubulointerstitial renal fibrosis is the common end point of progressive kidney diseases, and tubular epithelial-myofibroblast transdifferentiation （TEMT） plays a key role in the progress of tubulointerstitial renal fibrosis. Anaphylatoxin C3a and C5a are identified as novel profibrotic factors in renal disease and as potential new therapeutic targets. The aim of this study was to investigate whether C3a, C5a can regulate TEMT by transforming growth factor-β1 （TGF-β1）/connective tissue growth factor （CTGF） signaling pathway and the effects of C3a and C5a receptor antagonists （C3aRA and C5aRA） on C3α- and C5α-induced TEMT. Methods HK-2 cells were divided into C3a and C5a groups which were subdivided into four subgroups： control group, 10 ng/ml TGF-I31 group, 50 nmol/L C3a group, 50 nmol/L C3a plus 1 pmol/L C3aRA group; control group, 10 ng/ml TGF-I^I group, 50 nmol/L C5a group, 50 nmol/L C5a plus 2.5 pmol/L C5aRA group. TGF-β1 receptor antagonist （TGF-β1 RA） 10 IJg/ml was used to investigate the mechanism of C3α- and C5α-induced TEMT. Electron microscopy was used to observe the morphological changes. Immunocytochemistry staining, real-time PCR and Western blotting were used to detect the expressions of a smooth muscle actin （α-SMA）, E-cadherin, Col-I, C3a receptor （C3aR）, C5aR, CTGF and TGF-β1. Results HK-2 cells cultured with C3a and C5a for 72 hours exhibited strong staining of α-SMA, lost the positive staining of E-cadherin, and showed a slightly spindle-like shape and loss of microvilli on the cell surface. The expressions of α-SMA, E-cadherin, Col-I, C3aR, C5aR, TGF-β1 and CTGF in C3α- and C5α-treated groups were higher than normal control group （P 〈0.05）. C3aRA and C5aRA inhibited the expressions of α-SMA, Col-I, C3aR, C5aR, and up-regulated the expression of E-cadherin （P 〈0.05）. TGF-β1 and CTGF mRNA expressions induced by C3a and C5a were partly blocked by TGF-β1 RA （P 〈0.05）. Conclusion C3a and C5a can induce TEMT via the up-regu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展开更多
文摘Bckground Stem cells, which have the ability to differentiate into insulin-producing cells （IPCs）, would provide a potentially unlimited source of islet cells for transplantation and alleviate the major limitations of availability and allogeneic rejection. Therefore, the utilization of stem cells is becoming the most promising therapy for diabetes mellitus （DM）. Here, we studied the differentiation capacity of the diabetic patient＇s bone marrow-derived mesenchymal stem cells （MSCs） and tested the feasibility of using MSCs for β-cell replacement. Methods Bone marrow-derived MSCs were obtained from 10 DM patients （5 type 1 DM and 5 type 2 DM） and induced to IPCs under a three-stage protocol. Representative cell surface antigen expression profiles of MSCs were analysed by flow cytometric analysis. Reverse transcription-polymerase chain reaction （RT-PCR） was performed to detect multiple genes related to pancreatic β-cell development and function. The identity of the IPCs was illustrated by the analysis of morphology, ditizone staining and immunocytochemistry. Release of insulin by these cells was confirmed by immunoradioassay. Results Flow cytometric analysis of MSCs at passage 3 showed that these cells expressed high levels of CD29 （98.28%）, CD44 （99.56%） and CD106 （98.34%）. Typical islet-like cell clusters were observed at the end of the protocol （18 days）. Ditizone staining and immunohistochemistry for insulin were both positive. These differentiated cells at stage 2 （10 days） expressed nestin, pancreatic duodenal homeobox-1 （PDX-1）, Neurogenin3, Pax4, insulin, glucagon, but at stage 3 （18 days） we observed the high expression of PDX-1, insulin, glucagon. Insulin was secreted by these cells in response to different concentrations of glucose stimulation in a regulated manner （P〈0.05）. Conclusions Bone marrow-derived MSCs from DM patients can differentiate into functional IPCs under certain conditions in vitro. Using diabetic patient＇s own bone marrow-deriv
基金Supported by the ALIVE Foundation, the FIS from Instituto de Salud Carlos III, Spain, No. 03/0339, and the European Commission, No. LSHB-CT-2004-504761
文摘AIM： To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells （ADSC） and bone marrow-derived mesenchymal stem cells （BMSC） in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS： BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically analysed.RESULTS： BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors （C/EBPβ and HNF4α）, as demonstrated by adenoviral expression vectors.CONCLUSION： Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.
文摘Barrett's esophagus is a premalignant condition caused by gastroesophageal reflux. Once developed, it can progress through varying grades of dysplasia to esoph-ageal adenocarcinoma. Whilst it is well accepted that Barrett's esophagus is caused by gastroesophageal reflux, the molecular mechanisms of its pathogenesis and progression to cancer remain unclear. MicroRNAs (miRNAs) are short segments of RNA that have been shown to control the expression of many human genes. They have been implicated in most cellular processes, and the role of miRNAs in disease development is be-coming increasingly evident. Understanding altered miRNA expression is likely to help unravel the molecular mechanisms that underpin the development of Barrett's esophagus and its progression to cancer.
基金This study was supported by research grants from the National Natural Science Foundation of China(NO.81471475).
文摘The programmed cell death-1(PD-1)/PD-ligand 1(PD-L1)pathway is critical for normal pregnancy by promoting regulatory T(Treg)cell development and inhibiting the Th17 response.However,the relationship between the PD-1/PD-L1 pathway and the Treg/Th17 imbalance in pre-eclampsia(PE)is an enigma.In this study,decreased PD-1 and PD-L1 expression and a Treg/Th17 imbalance were observed at the maternal-fetal interface in PE.The regulatory effects of the PD-1/PD-L1 pathway on the Treg and Th17 cell quantities were determined in vitro by targeting T-cell proliferation,differentiation and transdifferentiation.First,decreased PD-1 expression might contribute to a higher Th17 cell frequency by promoting proliferation in PE.Second,the percentages of Treg but not Th17 cells differentiated from peripheral naive CD4+T cells were increased by PD-L1 Fc administration.This effect was accompanied by decreased PI3K/AKT/m-TOR and increased PTEN mRNA expression and was completely reversed by PD-1 blockade.Finally,the percentage of IL-17-producing Treg cells increased and was positively associated with the Th17 cell frequency in PE.Increased RORγt and IL-17 but not Foxp3 and IL-10 mRNA expression by Treg cells was observed with PD-1 blockade.Similar findings occurred when Treg cells were exposed to IL-6/IL-23/IL-1βand were reversed by PD-L1 Fc.Taken together,our findings indicate that the PD-1/PD-L1 pathway contributes to the Treg/Th17 imbalance via‘one-two punch’approaches:(i)promoting Th17 cell proliferation,(ii)inhibiting Treg cell differentiation and(iii)enhancing Treg cell plasticity into Th17 cells in PE.The therapeutic value of PD-L1 Fc for PE treatment will be explored in the future.
基金Supported by the Natural Science Foundation of Jilin Province of China,No.20190201010JC
文摘Liver fibrosis is a wound-healing response to chronic injuries, characterized by the excessive accumulation of extracellular matrix or scar tissue within the liver;in addition, its formation is associated with multiple cytokines as well as several cell types and a variety of signaling pathways. When liver fibrosis is not well controlled, it can progress to liver cirrhosis, but it is reversible in principle. Thus far, no efficient therapy is available for treatment of liver fibrosis. Although liver transplantation is the preferred strategy, there are many challenges remaining in this approach, such as shortage of donor organs, immunological rejection, and surgical complications. Hence, there is a great need for an alternative therapeutic strategy. Currently, mesenchymal stem cell (MSC) therapy is considered a promising therapeutic strategy for the treatment of liver fibrosis;advantageously, the characteristics of MSCs are continuous self-renewal, proliferation, multipotent differentiation, and immunomodulatory activities. The human umbilical cord-derived (hUC)-MSCs possess not only the common attributes of MSCs but also more stable biological characteristics, relatively easy accessibility, abundant source, and no ethical issues (e.g., bone marrow being the adult source), making hUC-MSCs a good choice for treatment of liver fibrosis. In this review, we summarize the biological characteristics of hUC-MSCs and their paracrine effects, exerted by secretion of various cytokines, which ultimately promote liver repair through several signaling pathways. Additionally, we discuss the capacity of hUC-MSCs to differentiate into hepatocyte-like cells for compensating the function of existing hepatocytes, which may aid in amelioration of liver fibrosis. Finally, we discuss the current status of the research field and its future prospects.
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
文摘Background Tubulointerstitial renal fibrosis is the common end point of progressive kidney diseases, and tubular epithelial-myofibroblast transdifferentiation （TEMT） plays a key role in the progress of tubulointerstitial renal fibrosis. Anaphylatoxin C3a and C5a are identified as novel profibrotic factors in renal disease and as potential new therapeutic targets. The aim of this study was to investigate whether C3a, C5a can regulate TEMT by transforming growth factor-β1 （TGF-β1）/connective tissue growth factor （CTGF） signaling pathway and the effects of C3a and C5a receptor antagonists （C3aRA and C5aRA） on C3α- and C5α-induced TEMT. Methods HK-2 cells were divided into C3a and C5a groups which were subdivided into four subgroups： control group, 10 ng/ml TGF-I31 group, 50 nmol/L C3a group, 50 nmol/L C3a plus 1 pmol/L C3aRA group; control group, 10 ng/ml TGF-I^I group, 50 nmol/L C5a group, 50 nmol/L C5a plus 2.5 pmol/L C5aRA group. TGF-β1 receptor antagonist （TGF-β1 RA） 10 IJg/ml was used to investigate the mechanism of C3α- and C5α-induced TEMT. Electron microscopy was used to observe the morphological changes. Immunocytochemistry staining, real-time PCR and Western blotting were used to detect the expressions of a smooth muscle actin （α-SMA）, E-cadherin, Col-I, C3a receptor （C3aR）, C5aR, CTGF and TGF-β1. Results HK-2 cells cultured with C3a and C5a for 72 hours exhibited strong staining of α-SMA, lost the positive staining of E-cadherin, and showed a slightly spindle-like shape and loss of microvilli on the cell surface. The expressions of α-SMA, E-cadherin, Col-I, C3aR, C5aR, TGF-β1 and CTGF in C3α- and C5α-treated groups were higher than normal control group （P 〈0.05）. C3aRA and C5aRA inhibited the expressions of α-SMA, Col-I, C3aR, C5aR, and up-regulated the expression of E-cadherin （P 〈0.05）. TGF-β1 and CTGF mRNA expressions induced by C3a and C5a were partly blocked by TGF-β1 RA （P 〈0.05）. Conclusion C3a and C5a can induce TEMT via the up-regu
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
