Objective:To investigate the effect of shikonin on the proliferation, apoptosis and extracellular matrix (ECM) of human mesangial cells (MC). Methods: MC was cultured in vitro with different concentrations of glucose ...Objective:To investigate the effect of shikonin on the proliferation, apoptosis and extracellular matrix (ECM) of human mesangial cells (MC). Methods: MC was cultured in vitro with different concentrations of glucose (30, 50, 80 mmol/L). The cell growth was observed by using MTT method and apoptosis by using an aunexin-V-Fluos. Immunohistochemical studies for Laminin (LN), Fibronectin (FN) and type Ⅳ Collagens (Col Ⅳ) were measured. Results: Shikonin inhibited their growth (P<0.05) and apoptosis in the glycated cultured cells. Shikonin 0.05 mmol/L significantly reduced the secretion of LN, FN and Col Ⅳ from MC (P<0.05) cultured in 30, 50 and 80 mmol/L glucose. Conclusion: Shikonin could prevent or treat diabetic nephropathy (DN) and glomerulosclerosis (GS).展开更多
The capacity for self-renewal and differentiation of human embryonic stem (ES) cells makes them a potential source for generation of pancreatic beta cells for treating type I diabetes mellitus. Here, we report a new...The capacity for self-renewal and differentiation of human embryonic stem (ES) cells makes them a potential source for generation of pancreatic beta cells for treating type I diabetes mellitus. Here, we report a newly developed and effective method, carried out in a serum-free system, which induced human ES cells to differentiate into insulin-producing cells. Activin A was used in the initial stage to induce definitive endoderm differentiation from human ES cells, as detected by the expression of the definitive endoderm markers Sox17 and Brachyury. Further, all-trans retinoic acid (RA) was used to promote pancreatic differentiation, as indicated by the expression of the early pancreatic transcription factors pdxl and hlxb9. After maturation in DMEM/F12 serum-free medium with bFGF and nicotinamide, the differentiated cells expressed islet specific markers such as C-peptide, insulin, glucagon and glut2. The percentage of C-peptide-positive cells exceeded 15%. The secretion of insulin and C-peptide by these cells corresponded to the variations in glucose levels. When transplanted into renal capsules of Streptozotocin (STZ)-treated nude mice, these differentiated human ES cells survived and maintained the expression of beta cell marker genes, including C-peptide, pdxl, glucokinase, nkx6.1, lAPP, pax6 and Tcfl. Thirty percent of the transplanted nude mice exhibited apparent restoration of stable euglycemia; and the corrected phenotype was sustained for more than six weeks. Our new method provides a promising in vitro differentiation model for studying the mechanisms of human pancreas development and illustrates the potential of using human ES cells for the treatment of type I diabetes mellitus.展开更多
Although Activin/Nodal signaling regulates pluripotency of human embryonic stem (ES) cells, how this signaling acts in mouse ES cells remains largely unclear. To investigate this, we confirmed that mouse ES cells po...Although Activin/Nodal signaling regulates pluripotency of human embryonic stem (ES) cells, how this signaling acts in mouse ES cells remains largely unclear. To investigate this, we confirmed that mouse ES cells possess active Smad2-mediated Activin/Nodal signaling and found that Smad2-mediated Activin/Nodal signaling is dispensable for self-renewal maintenance but is required for proper differentiation toward the mesendoderm lineage. To gain insights into the underlying mechanisms, Smad2-associated genes were identified by genome-wide chromatin immu- noprecipitation-chip analysis. The results showed that there is a transcriptional correlation between Smad2 binding and Activin/Nodal signaling modulation, and that the development-related genes were enriched among the Smad2- bound targets. We further identified Tapbp as a key player in mesendoderm differentiation of mouse ES cells acting downstream of the Activin/Nodal-Smad2 pathway. Taken together, our findings suggest that Smad2-mediated Activin/Nodal signaling orchestrates mesendoderm lineage commitment of mouse ES cells through direct modulation of corresponding developmental regulator expression.展开更多
We report a case of gastric choriocarcinoma admixed with an α-fetoprotein (AFP)-producing adeno-carcinoma. A 70-year-old man was hospitalized for gastric cancer that was detected during screening by esophagogastroduo...We report a case of gastric choriocarcinoma admixed with an α-fetoprotein (AFP)-producing adeno-carcinoma. A 70-year-old man was hospitalized for gastric cancer that was detected during screening by esophagogastroduodenoscopy (EGD). Initial laboratory data showed the increased serum level of AFP and EGD revealed a 5-cm ulcerofungating mass in the greater curvature of the gastric antrum. The patient underwent radical subtotal gastrectomywith D2 lymph node dissection and Billroth gastrojejunostomy. Histopathological evaluation confirmed double primary gastric cancer: gastric choriocarcinoma admixed with an AFP-producing adenocarcinoma and separated adenocarcinoma. At 2 wk postoperatively, his human chorionic gonadotropin and AFP levels had reduced and six cycles of adjuvant chemotherapy were initiated. No recurrence or distant metastasis was observed at 4 years postoperatively.展开更多
Neurotensin was found present in human early placenta using RIA and its release was demonstrated by in vitro perfusion experiment.Immunohistochemical staining revealed lots of NT-positive granules in early placental ...Neurotensin was found present in human early placenta using RIA and its release was demonstrated by in vitro perfusion experiment.Immunohistochemical staining revealed lots of NT-positive granules in early placental villi. Functional testing displayed NT′s inhibitory effect on release of hCG and progesterone from incubated early placenta. This result suggests the potential use of NT as an agent for terminating early pregnancy.展开更多
A paracrine regulation was recently proposed in human embryonic stem cells (hESCs) grown in mouse embryonic fibroblast (MEF)-conditioned media (MEF-CM), where hESCs spontaneously differentiate into autologous fi...A paracrine regulation was recently proposed in human embryonic stem cells (hESCs) grown in mouse embryonic fibroblast (MEF)-conditioned media (MEF-CM), where hESCs spontaneously differentiate into autologous fibroblastlike cells to maintain culture homeostasis by producing TGF-β and insulin-like growth factor-lI (IGF-Ⅱ) in response to basic fibroblast growth factor (bFGF). Although the importance of TGF-β family members in the maintenance of pluripotency of hESCs is widely established, very little is known about the role of IGF-Ⅱ. In order to ease hESC cul- ture conditions and to reduce xenogenic components, we sought (i) to determine whether hESCs can be maintained stable and pluripotent using CM from human foreskin fibroblasts (HFFs) and human mesenchymal stem cells (hM- SCs) rather than MEF-CM, and (ii) to analyze whether the cooperation of bFGF with TGF-β and IGF-Ⅱ to maintain hESCs in MEF-CM may be extrapolated to hESCs maintained in allogeneic mesenchymal stem cell (MSC)-CM and HFF-CM. We found that MSCs and HFFs express all FGF receptors (FGFR1-4) and specifically produce TGF-β in response to bFGF. However, HFFs but not MSCs secrete IGF-Ⅱ. Despite the absence of IGF-Ⅱ in MSC-CM, hESC pluripotency and culture homeostasis were successfully maintained in MSC-CM for over 37 passages. Human ESCs derived on MSCs and hESCs maintained in MSC-CM retained hESC morphology, euploidy, expression of surface markers and transcription factors linked to pluripotency and displayed in vitro and in vivo multilineage developmental potential, suggesting that IGF-Ⅱ may be dispensable for hESC pluripotency. In fact, IGF-Ⅱ blocking had no effect on the homeostasis of hESC cultures maintained either on HFF-CM or on MSC-CM. These data indicate that hESCs are successfully maintained feeder-free with IGF-Ⅱ-lacking MSC-CM, and that the previously proposed paracrine mechanism by which bFGF cooperates with TGF-β and IGF-Ⅱ in the maintenance of hESCs in MEF-CM may not be fully extrapolated to hESCs maintained in CM from human MSCs.展开更多
OBJECTIVE:To study the effect of puerarin on matrix metalloproteinase-2(MMP-2)gene and protein expression in human fetal scleral fibroblasts(HFSFs)exposed to extremely low frequency electromagnetic fields(ELF-EMF).MET...OBJECTIVE:To study the effect of puerarin on matrix metalloproteinase-2(MMP-2)gene and protein expression in human fetal scleral fibroblasts(HFSFs)exposed to extremely low frequency electromagnetic fields(ELF-EMF).METHODS:Cultured HFSFs were exposed to 0.2mT ELF-EMF for 24 h.The experimental groups were divided into subgroups treated with 0,0.1,1and 10μM puerarin respectively.The expression of MMP-2 mRNA and protein were detected with real-time polymerase chain reaction and western-blot analysis respectively.RESULTS:MMP-2 mRNA and protein expression increased by 0.793 and 1.130 folds respectively under the exposure of ELF-EMFs at 0.2 mT flux density for24 h.Puerarin at the concentration of 0.1μM reversed this effect by 8.53%in mRNA and by 17.97%in protein expression(P<0.05).The effect was more prominent at higher concentrations(1 and 10μM,P<0.01).CONCLUSION:Exposure to ELF-EMFs increased the expression of MMP-2 mRNA and protein in HFSF cells.Puerarin reversed the action to some extent in a specific concentration range.Our results implied that the puerarin might protect scleral tissue from increased expression induced by exposure to ELF-EMFs.展开更多
文摘Objective:To investigate the effect of shikonin on the proliferation, apoptosis and extracellular matrix (ECM) of human mesangial cells (MC). Methods: MC was cultured in vitro with different concentrations of glucose (30, 50, 80 mmol/L). The cell growth was observed by using MTT method and apoptosis by using an aunexin-V-Fluos. Immunohistochemical studies for Laminin (LN), Fibronectin (FN) and type Ⅳ Collagens (Col Ⅳ) were measured. Results: Shikonin inhibited their growth (P<0.05) and apoptosis in the glycated cultured cells. Shikonin 0.05 mmol/L significantly reduced the secretion of LN, FN and Col Ⅳ from MC (P<0.05) cultured in 30, 50 and 80 mmol/L glucose. Conclusion: Shikonin could prevent or treat diabetic nephropathy (DN) and glomerulosclerosis (GS).
基金This research was supported by the Ministry of Science and Technology Grant (2001CB510106);Science and Technology Plan of Beijing Municipal Government (H020220050290);National Natural Science Foundation of China Awards for 0utstanding Young Scientists (30125022);for Creative Research Groups (30421004);Bill & Melinda Gates Foundation Grant (37871) to H Deng.
文摘The capacity for self-renewal and differentiation of human embryonic stem (ES) cells makes them a potential source for generation of pancreatic beta cells for treating type I diabetes mellitus. Here, we report a newly developed and effective method, carried out in a serum-free system, which induced human ES cells to differentiate into insulin-producing cells. Activin A was used in the initial stage to induce definitive endoderm differentiation from human ES cells, as detected by the expression of the definitive endoderm markers Sox17 and Brachyury. Further, all-trans retinoic acid (RA) was used to promote pancreatic differentiation, as indicated by the expression of the early pancreatic transcription factors pdxl and hlxb9. After maturation in DMEM/F12 serum-free medium with bFGF and nicotinamide, the differentiated cells expressed islet specific markers such as C-peptide, insulin, glucagon and glut2. The percentage of C-peptide-positive cells exceeded 15%. The secretion of insulin and C-peptide by these cells corresponded to the variations in glucose levels. When transplanted into renal capsules of Streptozotocin (STZ)-treated nude mice, these differentiated human ES cells survived and maintained the expression of beta cell marker genes, including C-peptide, pdxl, glucokinase, nkx6.1, lAPP, pax6 and Tcfl. Thirty percent of the transplanted nude mice exhibited apparent restoration of stable euglycemia; and the corrected phenotype was sustained for more than six weeks. Our new method provides a promising in vitro differentiation model for studying the mechanisms of human pancreas development and illustrates the potential of using human ES cells for the treatment of type I diabetes mellitus.
基金Acknowledgments We thank Gaoyang Zhu for technical assistance. This work was supported by grants from the National Natural Science Foundation of China (30930050, 30921004), the 973 Program (2006CB943401, 2010CB833706) to YGC, and grants from the China National Science Foundation (Grant # 30890033, 30588001 and 30620120433), Chinese Ministry of Science and Technology(Grant # 2006CB910700) to JDH.
文摘Although Activin/Nodal signaling regulates pluripotency of human embryonic stem (ES) cells, how this signaling acts in mouse ES cells remains largely unclear. To investigate this, we confirmed that mouse ES cells possess active Smad2-mediated Activin/Nodal signaling and found that Smad2-mediated Activin/Nodal signaling is dispensable for self-renewal maintenance but is required for proper differentiation toward the mesendoderm lineage. To gain insights into the underlying mechanisms, Smad2-associated genes were identified by genome-wide chromatin immu- noprecipitation-chip analysis. The results showed that there is a transcriptional correlation between Smad2 binding and Activin/Nodal signaling modulation, and that the development-related genes were enriched among the Smad2- bound targets. We further identified Tapbp as a key player in mesendoderm differentiation of mouse ES cells acting downstream of the Activin/Nodal-Smad2 pathway. Taken together, our findings suggest that Smad2-mediated Activin/Nodal signaling orchestrates mesendoderm lineage commitment of mouse ES cells through direct modulation of corresponding developmental regulator expression.
文摘We report a case of gastric choriocarcinoma admixed with an α-fetoprotein (AFP)-producing adeno-carcinoma. A 70-year-old man was hospitalized for gastric cancer that was detected during screening by esophagogastroduodenoscopy (EGD). Initial laboratory data showed the increased serum level of AFP and EGD revealed a 5-cm ulcerofungating mass in the greater curvature of the gastric antrum. The patient underwent radical subtotal gastrectomywith D2 lymph node dissection and Billroth gastrojejunostomy. Histopathological evaluation confirmed double primary gastric cancer: gastric choriocarcinoma admixed with an AFP-producing adenocarcinoma and separated adenocarcinoma. At 2 wk postoperatively, his human chorionic gonadotropin and AFP levels had reduced and six cycles of adjuvant chemotherapy were initiated. No recurrence or distant metastasis was observed at 4 years postoperatively.
文摘Neurotensin was found present in human early placenta using RIA and its release was demonstrated by in vitro perfusion experiment.Immunohistochemical staining revealed lots of NT-positive granules in early placental villi. Functional testing displayed NT′s inhibitory effect on release of hCG and progesterone from incubated early placenta. This result suggests the potential use of NT as an agent for terminating early pregnancy.
文摘A paracrine regulation was recently proposed in human embryonic stem cells (hESCs) grown in mouse embryonic fibroblast (MEF)-conditioned media (MEF-CM), where hESCs spontaneously differentiate into autologous fibroblastlike cells to maintain culture homeostasis by producing TGF-β and insulin-like growth factor-lI (IGF-Ⅱ) in response to basic fibroblast growth factor (bFGF). Although the importance of TGF-β family members in the maintenance of pluripotency of hESCs is widely established, very little is known about the role of IGF-Ⅱ. In order to ease hESC cul- ture conditions and to reduce xenogenic components, we sought (i) to determine whether hESCs can be maintained stable and pluripotent using CM from human foreskin fibroblasts (HFFs) and human mesenchymal stem cells (hM- SCs) rather than MEF-CM, and (ii) to analyze whether the cooperation of bFGF with TGF-β and IGF-Ⅱ to maintain hESCs in MEF-CM may be extrapolated to hESCs maintained in allogeneic mesenchymal stem cell (MSC)-CM and HFF-CM. We found that MSCs and HFFs express all FGF receptors (FGFR1-4) and specifically produce TGF-β in response to bFGF. However, HFFs but not MSCs secrete IGF-Ⅱ. Despite the absence of IGF-Ⅱ in MSC-CM, hESC pluripotency and culture homeostasis were successfully maintained in MSC-CM for over 37 passages. Human ESCs derived on MSCs and hESCs maintained in MSC-CM retained hESC morphology, euploidy, expression of surface markers and transcription factors linked to pluripotency and displayed in vitro and in vivo multilineage developmental potential, suggesting that IGF-Ⅱ may be dispensable for hESC pluripotency. In fact, IGF-Ⅱ blocking had no effect on the homeostasis of hESC cultures maintained either on HFF-CM or on MSC-CM. These data indicate that hESCs are successfully maintained feeder-free with IGF-Ⅱ-lacking MSC-CM, and that the previously proposed paracrine mechanism by which bFGF cooperates with TGF-β and IGF-Ⅱ in the maintenance of hESCs in MEF-CM may not be fully extrapolated to hESCs maintained in CM from human MSCs.
基金Supported by the General Program of the Bio-medical Division of the Shanghai Science and Technology Commission(10411966200)the Scientific Research Fund of Chinese Medical of Shanghai Health Bureau(2009s023)the Shanghai Leading Academic Discipline Project(S30205)
文摘OBJECTIVE:To study the effect of puerarin on matrix metalloproteinase-2(MMP-2)gene and protein expression in human fetal scleral fibroblasts(HFSFs)exposed to extremely low frequency electromagnetic fields(ELF-EMF).METHODS:Cultured HFSFs were exposed to 0.2mT ELF-EMF for 24 h.The experimental groups were divided into subgroups treated with 0,0.1,1and 10μM puerarin respectively.The expression of MMP-2 mRNA and protein were detected with real-time polymerase chain reaction and western-blot analysis respectively.RESULTS:MMP-2 mRNA and protein expression increased by 0.793 and 1.130 folds respectively under the exposure of ELF-EMFs at 0.2 mT flux density for24 h.Puerarin at the concentration of 0.1μM reversed this effect by 8.53%in mRNA and by 17.97%in protein expression(P<0.05).The effect was more prominent at higher concentrations(1 and 10μM,P<0.01).CONCLUSION:Exposure to ELF-EMFs increased the expression of MMP-2 mRNA and protein in HFSF cells.Puerarin reversed the action to some extent in a specific concentration range.Our results implied that the puerarin might protect scleral tissue from increased expression induced by exposure to ELF-EMFs.