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1.
Lancet Diabetes Endocrinol ; 2(12): 935-43, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25081582

ABSTRACT

BACKGROUND: The prevalence of diabetes is increasing in young adults in Asia, but little is known about metabolic control or the burden of associated complications in this population. We assessed the prevalence of young-onset versus late-onset type 2 diabetes, and associated risk factors and complication burdens, in the Joint Asia Diabetes Evaluation (JADE) cohort. METHODS: JADE is an ongoing prospective cohort study. We enrolled adults with type 2 diabetes from 245 outpatient clinics in nine Asian countries or regions. We classified patients as having young-onset diabetes if they were diagnosed before the age of 40 years, and as having late-onset diabetes if they were diagnosed at 40 years or older. Data for participants' first JADE assessment was extracted for cross-sectional analysis. We compared clinical characteristics, metabolic risk factors, and the prevalence of complications between participants with young-onset diabetes and late-onset diabetes. FINDINGS: Between Nov 1, 2007, and Dec 21, 2012, we enrolled 41,029 patients (15,341 from Hong Kong, 9107 from India, 7712 from Philippines, 5646 from China, 1751 from South Korea, 705 from Vietnam, 385 from Singapore, 275 from Thailand, 107 from Taiwan). 7481 patients (18%) had young-onset diabetes, with age at diagnosis of mean 32·9 years [SD 5·7] versus 53·9 years [9·0] with late-onset diabetes (n=33,548). Those with young-onset diabetes had longer disease duration (median 10 years [IQR 3-18]) than those with late-onset diabetes (5 years [2-11]). Fewer patients with young-onset diabetes achieved HbA1c concentrations lower than 7% compared to those with late-onset diabetes (27% vs 42%; p<0·0001) Patients with young-onset diabetes had higher mean concentrations of HbA1c (mean 8·32% [SD 2·03] vs 7·69% [1·82]; p<0·0001), LDL cholesterol (2·78 mmol/L [0·96] vs 2·74 [0·93]; p=0·009), and a higher prevalence of retinopathy (1363 [20%] vs 5714 (18%); p=0·011) than those with late-onset diabetes, but were less likely to receive statins (2347 [31%] vs 12,441 [37%]; p<0·0001) and renin-angiotensin-system inhibitors (1868 [25%] vs 9665 [29%]; p=0·006). INTERPRETATION: In clinic-based settings across Asia, one in five adult patients had young-onset diabetes. Compared with patients with late-onset diabetes, metabolic control in those with young-onset diabetes was poor, and fewer received organ-protective drugs. Given the risk conferred by long-term suboptimum metabolic control, our findings suggest an impending epidemic of young-onset diabetic complications. FUNDING: The Asia Diabetes Foundation (ADF) and Merck.


Subject(s)
Diabetes Mellitus, Type 2/metabolism , Adult , Age Factors , Asia/epidemiology , Cross-Sectional Studies , Diabetes Complications/epidemiology , Epidemics , Female , Humans , Male , Metabolome , Middle Aged , Odds Ratio , Prospective Studies , Risk Factors
2.
J Mol Med (Berl) ; 88(2): 183-92, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19806338

ABSTRACT

TCF7L2 genetic variants were associated with progression to type 2 diabetes in Europeans. However, the role of TCF7L2 in type 2 diabetes remained uncertain in Chinese. Seventeen tag single nucleotide polymorphisms were genotyped in 1,094 subjects of Chinese origin from the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance family study. At baseline, the rs7903146 T allele in the exon 4 linkage disequilibrium (LD) block were associated with lower insulinogenic index at 60 min (P = 0.01), while the rs290481 G allele near the 3' end was associated with higher 2-h post-challenge glucose (P = 0.003) and insulin concentration (P = 0.02), elevated systolic (P = 0.01) and diastolic blood pressure (P = 0.006), lower waist circumference (P = 0.01), and increased steady-state plasma glucose (SSPG) concentration measured with modified insulin suppression test (P = 0.02). Over an average follow-up period of 5.43 years, participants with the rs7903146 T allele or variants in the same LD block, but not those with the rs290481 G allele, were more likely to progress to diabetes (hazard ratio = 2.61, 95% confidence interval, 1.27-5.39, P = 0.009) than were non-carriers. TCF7L2 gene expression was inversely associated with SSPG in human visceral (r = -0.73, P = 0.006) and subcutaneous adipose tissue (r = -0.62, P = 0.03). TCF7L2 may exert pleiotropic effects on insulin secretion or insulin resistance. However, only variants associated with impaired beta-cell function predict progression to diabetes in Chinese.


Subject(s)
Diabetes Mellitus, Type 2/ethnology , Diabetes Mellitus, Type 2/genetics , Genetic Variation , Insulin Resistance , Insulin/metabolism , TCF Transcription Factors/genetics , Adult , Asian People , Cohort Studies , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/physiopathology , Disease Progression , Family , Female , Humans , Incidence , Insulin Secretion , Male , Middle Aged , Polymorphism, Single Nucleotide , TCF Transcription Factors/metabolism , Transcription Factor 7-Like 2 Protein
3.
J Biomed Mater Res A ; 86(4): 1097-105, 2008 Sep 15.
Article in English | MEDLINE | ID: mdl-18080299

ABSTRACT

Multipotential mesenchymal stem cells (MSCs) isolated from bone marrow can differentiate into multiple mesenchymal tissues and exhibit a neuronal phenotype under appropriate induction conditions. Methods promoting neural differentiation have been adapted to derive insulin producing cells (IPCs) from embryonic stem cells, but it remains unclear whether neuronal cell-based differentiation method will be able to derive IPCs from MSCs. Using a four-stage differentiation protocol which contains neuronal differentiation factor and IPC-conversion reagent-nicotinamide, the potential of human MSCs to differentiate into IPCs was evaluated by means of reverse transcription-polymerase chain reaction, immunostaining, and functional analysis. MSCs in monolayer spontaneously expressed genes for islet transcription factors, Nkx6.1 and Ngn3, but did not express insulin after treatment in this protocol. Pellet suspension culture and the addition of fibronectin enhanced pancreatic differentiation with increase in insulin and Glut2 gene expression. Switching of cells to high-glucose culture further increased immunostaining for proinsulin and insulin. IPCs secreted insulin in response to elevated glucose concentration, which was regulated by reagents that increase cyclic AMP production or modify calcium influx. Our data suggest that MSCs in the monolayer do not undergo IPC differentiation and pellet suspension culture with fibronectin promotes IPCs derived from MSCs.


Subject(s)
Cell Culture Techniques/methods , Cell Differentiation/drug effects , Fibronectins/pharmacology , Insulin-Secreting Cells/cytology , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Cell Aggregation/drug effects , Ectoderm/cytology , Ectoderm/drug effects , Gene Expression Regulation/drug effects , Glucose/pharmacology , Humans , Insulin/metabolism , Mesoderm/cytology , Mesoderm/drug effects , Neurons/cytology , Neurons/drug effects , Proinsulin/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
4.
World J Gastroenterol ; 13(11): 1672-9, 2007 Mar 21.
Article in English | MEDLINE | ID: mdl-17461469

ABSTRACT

AIM: To enhance the differentiation of insulin producing cell (IPC) ability from embryonic stem (ES) cells in vitro. METHODS: Four-day embryoid body (EB)-formatted ES cells were dissociated as single cells for the followed plasmid DNA delivery. The use of Nucleofector electroporator (Amaxa biosystems, Germany) in combination with medium-contained G418 provided a high efficiency of gene delivery for advanced selection. Neucleofected cells were plated on the top of fibronectin-coated Petri dishes. Addition of Ly294002 and raised the glucose in medium at 24 h before examination. The differentiation status of these cells was monitored by semi-quantitative PCR (SQ-PCR) detection of the expression of relative genes, such as oct-4, sox-17, foxa2, mixl1, pdx-1, insulin 1, glucagons and somatostatin. The percentage of IPC population on d 18 of the experiment was investigated by immunohistochemistry (IHC), and the content/secretion of insulin was estimated by ELISA assay. The mice with severe combined immunodeficiency disease (SCID) pretreated with streptozotocin (STZ) were used to eliminate plasma glucose restoration after pax4+ ES implantation. RESULTS: A high efficiency of gene delivery was demonstrated when neucleofection was used in the present study; approximately 70% cells showed DsRed expression 2 d after neucleofection. By selection of medium-contained G418, the percentage of DsRed expressing cells kept high till the end of study. The pancreatic differentiation seemed to be accelerated by pax4 nucleofection. When compared to the group of cells with mock control, foxa2, mixl1, pdx1, higher insulin and somatostatin levels were detected by SQ-PCR 4 d after nucleofection in the group of pax4 expressing plasmid delivery. Approximately 55% of neucleofected cells showed insulin expression 18 d after neucleofection, and only 18% of cells showed insulin expression in mock control. The disturbance was shown by nucleofected pax4 RNAi vector; only 8% of cells expressed insulin 18 d after nucleofection. A higher IPC population was also detected in the insulin content by ELISA assay, and the glucose dependency was demonstrated in insulin secretion level. In the animal model, improvement of average plasma glucose concentration was observed in the group of pax-4 expressed ES of SCID mice pretreated with STZ, but no significant difference was observed in the group of STZ-pretreated SCID mice who were transplanted ES with mock plasmid. CONCLUSION: Enhancement of IPC differentiation from EB-dissociated ES cells can be revealed by simply using pax4 expressing plasmid delivery. Not only more IPCs but also pancreatic differentiation-related genes can be detected by SQ-PCR. Expression of relative genes, such as foxa 2, mixl 1, pdx-1, insulin 1 and somatostatin after nucleofection, suggests that pax4 accelerates the whole differentiation progress. The higher insulin production with glucose dependent modulation suggests that pax4 expression can drive more mature IPCs. Although further determination of the entire mechanism is required, the potential of pax-4-nucleofected cells in medical treatment is promising.


Subject(s)
Cell Differentiation/physiology , Embryonic Stem Cells/cytology , Embryonic Stem Cells/physiology , Homeodomain Proteins/physiology , Insulin/metabolism , Paired Box Transcription Factors/physiology , Transfection/methods , Animals , Blood Glucose/metabolism , Cells, Cultured , Gene Expression Regulation, Developmental , Hepatocyte Nuclear Factor 3-beta/genetics , Hepatocyte Nuclear Factor 3-beta/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Insulin/genetics , Mice , Mice, Inbred BALB C , Mice, SCID , Octamer Transcription Factor-3/genetics , Octamer Transcription Factor-3/metabolism , Paired Box Transcription Factors/genetics , Polymerase Chain Reaction/methods , Somatostatin/genetics , Somatostatin/metabolism , Trans-Activators/genetics , Trans-Activators/metabolism
5.
J Immunol ; 177(9): 6199-206, 2006 Nov 01.
Article in English | MEDLINE | ID: mdl-17056549

ABSTRACT

Human CMV (HCMV) is a widespread human pathogen that causes blindness by inducing retinitis in AIDS patients. Previously, we showed that viral immediate early 2 (IE2) protein may allow HCMV to evade the immune control by killing the Fas receptor-positive T lymphocytes attracted to the infected retina with increased secretion of Fas ligand (FasL). In this study, we further demonstrate that the secreted FasL also kills uninfected Fas-rich bystander retinal cells and that IE2 simultaneously protects the infected cells from undergoing apoptotic death, in part, by activating the expression of cellular FLIP (c-FLIP), an antiapoptotic molecule that blocks the direct downstream executer caspase 8 of the FasL/Fas pathway. c-FLIP induction requires the N-terminal 98 residues of IE2 and the c-FLIP promoter region spanning nucleotides -978 to -696. In vivo association of IE2 to this region, IE2-specific c-FLIP activation, and decrease of FasL-up-regulated activities of caspases 8 and 3 were all demonstrated in HCMV-infected human retinal cells. Moreover, c-FLIP up-regulation by IE2 appeared to involve PI3K and might also render cells resistant to TRAIL-mediated death. Finally, enhanced c-FLIP signals were immunohistochemically detected in IE-positive cells in the HCMV-infected lesions of the human retina. Taken together, these data demonstrate specific activation of c-FLIP by HCMV IE2 and indicate a novel role for c-FLIP in the pathogenesis of HCMV retinitis.


Subject(s)
Apoptosis/genetics , CASP8 and FADD-Like Apoptosis Regulating Protein/genetics , Cytomegalovirus Retinitis/genetics , Immediate-Early Proteins/metabolism , Trans-Activators/metabolism , Transcriptional Activation , CASP8 and FADD-Like Apoptosis Regulating Protein/analysis , Cells, Cultured , Cytomegalovirus Retinitis/metabolism , Fas Ligand Protein/metabolism , Humans , Immediate-Early Proteins/analysis , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Promoter Regions, Genetic , Retina/chemistry , Retina/metabolism , Retina/virology , Sequence Deletion , Trans-Activators/analysis , Up-Regulation
6.
World J Gastroenterol ; 12(28): 4529-35, 2006 Jul 28.
Article in English | MEDLINE | ID: mdl-16874866

ABSTRACT

AIM: To isolate putative pancreatic stem cells (PSCs) from human adult tissues of pancreas duct using serum-free, conditioned medium. The characterization of surface phenotype of these PSCs was analyzed by flow cytometry. The potential for pancreatic lineage and the capability of beta-cell differentiation in these PSCs were evaluated as well. METHODS: By using serum-free medium supplemented with essential growth factors, we attempted to isolate the putative PSCs which has been reported to express nestin and pdx-1. The Matrigel(TM) was employed to evaluate the differential capacity of isolated cells. Dithizone staining, insulin content/secretion measurement, and immunohistochemistry staining were used to monitor the differentiation. Fluorescence activated cell sorting (FACS) was used to detect the phenotypic markers of putative PSCs. RESULTS: A monolayer of spindle-like cells was cultivated. The putative PSCs expressed pdx-1 and nestin. They were also able to differentiate into insulin-, glucagon-, and somatostatin-positive cells. The spectrum of phenotypic markers in PSCs was investigated; a similarity was revealed when using human bone marrow-derived stem cells as the comparative experiment, such as CD29, CD44, CD49, CD50, CD51, CD62E, PDGFR-alpha, CD73 (SH2), CD81, CD105(SH3). CONCLUSION: In this study, we successfully isolated PSCs from adult human pancreatic duct by using serum-free medium. These PSCs not only expressed nestin and pdx-1 but also exhibited markers attributable to mesenchymal stem cells. Although work is needed to elucidate the role of these cells, the application of these PSCs might be therapeutic strategies for diabetes mellitus.


Subject(s)
Cell Lineage , Mesenchymal Stem Cells/cytology , Pancreas/cytology , Pancreatic Ducts/cytology , Bone Marrow Cells/cytology , Bone Marrow Cells/metabolism , Cell Differentiation/physiology , Cell Survival , Cells, Cultured , Diabetes Mellitus/therapy , Flow Cytometry , Gene Expression Regulation , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Insulin/metabolism , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/metabolism , Intermediate Filament Proteins/genetics , Intermediate Filament Proteins/metabolism , Mesenchymal Stem Cells/metabolism , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Nestin , Pancreas/metabolism , Pancreatic Ducts/metabolism , Stem Cell Transplantation , Trans-Activators/genetics , Trans-Activators/metabolism
7.
Br J Pharmacol ; 148(5): 587-98, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16702990

ABSTRACT

1. Moclobemide (MB) is an antidepressant drug that selectively and reversibly inhibits monoamine oxidase-A. Recent studies have revealed that antidepressant drugs possess the characters of potent growth-promoting factors for the development of neurogenesis and improve the survival rate of serotonin (5-hydroxytrytamine; 5-HT) neurons. However, whether MB comprises neuroprotection effects or modulates the proliferation of neural stem cells (NSCs) needs to be elucidated. 2. In this study, firstly, we used the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay to demonstrate that 50 microM MB can increase the cell viability of NSCs. The result of real-time reverse transcription-polymerase chain reaction (RT-PCR) showed that the induction of MB can upregulate the gene expressions of Bcl-2 and Bcl-xL. By using caspases 8 and 3, ELISA and terminal dUTP nick-end labeling (TUNEL) assay, our data further confirmed that 50 microM MB-treated NSCs can prevent FasL-induced apoptosis. 3. The morphological findings also supported the evidence that MB can facilitate the dendritic development and increase the neurite expansion of NSCs. Moreover, we found that MB treatment increased the expression of Bcl-2 in NSCs through activating the extracellular-regulated kinase (ERK) phosphorylation. 4. By using the triple-staining immunofluorescent study, the percentages of serotonin- and MAP-2-positive cells in the day 7 culture of MB-treated NSCs were significantly increased (P<0.01). Furthermore, our data supported that MB treatment increased functional production of serotonin in NSCs via the modulation of ERK1/2. In sum, the study results support that MB can upregulate Bcl-2 expression and induce the differentiation of NSCs into serotoninergic neuron via ERK pathway.


Subject(s)
Cell Differentiation/drug effects , Extracellular Signal-Regulated MAP Kinases/physiology , Moclobemide/pharmacology , Neurons/drug effects , Proto-Oncogene Proteins c-bcl-2/metabolism , Serotonin/metabolism , Stem Cells/drug effects , Animals , Apoptosis Regulatory Proteins/analysis , Apoptosis Regulatory Proteins/metabolism , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Enzyme-Linked Immunosorbent Assay , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation/drug effects , In Situ Nick-End Labeling , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Neurites/drug effects , Neurons/metabolism , Phosphorylation/drug effects , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction
8.
Cell Tissue Res ; 324(3): 457-66, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16505995

ABSTRACT

The expression of alpha-smooth muscle actin (SMA) by human mesenchymal stem cells (hMSCs) during chondrogenesis was investigated by the use of pellet culture. Undifferentiated hMSCs expressed low but detectable amounts of SMA and the addition of transforming growth factor beta1 (TGF-beta1) to the culture medium increased SMA expression in a dose-dependent manner. Differentiation in pellet culture was rapidly induced in the presence of TGF-beta1 and was accompanied by the development of annular layers at the surface of the pellet. These peripheral layers lacked expression of glycosaminoglycan and type II collagen during early differentiation. Progress in differentiation increased the synthesis of glycosaminoglycan and type II collagen and the expression of SMA in these layers. Double-staining for type II collagen and SMA by immunofluorescence demonstrated the differentiation of hMSCs into cells positive for these two proteins. The addition of cytochalasin D, a potent inhibitor of the polymerization of actin microfilaments, caused damage to the structural integrity and surface smoothness of the chondrogenic pellets. The SMA-positive cells in the peripheral layers of the chondrogenic pellets mimic those within the superficial layer of articular cartilage and are speculated to play a major role in cartilage development and maintenance.


Subject(s)
Actins/biosynthesis , Chondrocytes/physiology , Chondrogenesis , Mesenchymal Stem Cells/physiology , Actins/antagonists & inhibitors , Cartilage, Articular/metabolism , Cell Differentiation , Cells, Cultured , Chondrocytes/cytology , Chondrocytes/metabolism , Collagen Type II/biosynthesis , Cytochalasin D/pharmacology , Endothelial Cells/cytology , Endothelial Cells/physiology , Female , Glycosaminoglycans/biosynthesis , Humans , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Middle Aged , Myocytes, Smooth Muscle/metabolism , Protein Isoforms/biosynthesis , Transforming Growth Factor beta1/pharmacology
9.
Biochem Biophys Res Commun ; 343(2): 391-400, 2006 May 05.
Article in English | MEDLINE | ID: mdl-16545775

ABSTRACT

Fluoxetine is a widely used antidepressant compound which inhibits the reuptake of serotonin in the central nervous system. Recent studies have shown that fluoxetine can promote neurogenesis and improve the survival rate of neurons. However, whether fluoxetine modulates the proliferation or neuroprotection effects of neural stem cells (NSCs) needs to be elucidated. In this study, we demonstrated that 20 microM fluoxetine can increase the cell proliferation of NSCs derived from the hippocampus of adult rats by MTT test. The up-regulated expression of Bcl-2, Bcl-xL and the cellular FLICE-inhibitory protein (c-FLIP) in fluoxetine-treated NSCs was detected by real-time RT-PCR. Our results further showed that fluoxetine protects the lipopolysaccharide-induced apoptosis in NSCs, in part, by activating the expression of c-FLIP. Moreover, c-FLIP induction by fluoxetine requires the activation of the c-FLIP promoter region spanning nucleotides -414 to -133, including CREB and SP1 sites. This effect appeared to involve the phosphatidylinositol-3-kinase-dependent pathway. Furthermore, fluoxetine treatment significantly inhibited the induction of proinflammatory factor IL-1beta, IL-6, and TNF-alpha in the culture medium of LPS-treated NSCs (p<0.01). The results of high performance liquid chromatography coupled to electrochemical detection further confirmed that fluoxentine increased the functional production of serotonin in NSCs. Together, these data demonstrate the specific activation of c-FLIP by fluoxetine and indicate the novel role of fluoxetine for neuroprotection in the treatment of depression.


Subject(s)
Caspases/metabolism , Cytokines/metabolism , Fluoxetine/administration & dosage , Hippocampus/physiology , Neurons/physiology , Stem Cells/physiology , Animals , Apoptosis/drug effects , Caspase 8 , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Hippocampus/cytology , Hippocampus/drug effects , Lipopolysaccharides/administration & dosage , Neurons/drug effects , Rats , Rats, Sprague-Dawley , Stem Cells/drug effects , Up-Regulation/drug effects , Up-Regulation/physiology
10.
Cell Signal ; 18(4): 519-30, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16098715

ABSTRACT

Recent in vivo transplantation studies have shown that mesenchymal stem cells (MSCs) were able to differentiate into mesoderm-derived cell types as well as cells with neuroectodermal characteristics, suggesting that transdifferentiation occurs in the mammalian system. We have reported an immortalized line of human MSCs (hMSCs), KP-hMSCs, which expresses CD29, CD44, CD90, and CD105, and complies with the characteristics shared by mere hMSCs. In a current experiment, we further demonstrated that expanded KP-hMSCs exhibited markers of neuroepithelial or neural precursor cells, such as Nestin, Musashi-1, Vimentin, NCAM, Pax-6, and Sox-9. KP-hMSCs simultaneously expressed proteins of the neuronal, astrocyte, and oligodendrocyte lineages during culture expansion; in addition, they initiated neurite outgrowth and eradicated protein expressions of astrocyte and oligodendrocyte lineages in response to the elevated signaling of the cAMP-PKA pathway after serum depletion in a defined neural induction medium. From the current results, KP-hMSCs may be used to elucidate molecular signaling on the neural differentiation of adult human non-neural tissues. We also presented evidence for the possibility that adult MSCs and fetal neuroepithelial or neural precursor cells both provide for the continual maintenance and repair of the postnatal neural tissues and may derive from the same origin or have one deriving from the other.


Subject(s)
Mesenchymal Stem Cells/metabolism , Neurites/metabolism , Signal Transduction/physiology , 1-Methyl-3-isobutylxanthine/pharmacology , Colforsin/pharmacology , Cyclic AMP Response Element-Binding Protein/metabolism , Cyclic AMP-Dependent Protein Kinases/drug effects , Cyclic AMP-Dependent Protein Kinases/metabolism , Female , Humans , Mesenchymal Stem Cells/drug effects , Middle Aged , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Neurites/drug effects , Phosphorylation , Signal Transduction/drug effects , Time Factors
11.
J Biomed Mater Res A ; 74(3): 439-46, 2005 Sep 01.
Article in English | MEDLINE | ID: mdl-16013059

ABSTRACT

Previous reports have demonstrated the suitability of alginate microencapsulation for chondrogenesis of human mesenchymal stem cells (MSCs) in vitro. This study examined the MSCs-alginate constructs that were transplanted beneath the dorsal skin of nude mice for 8 weeks after a variety of in vitro culture periods. The in vitro culture had great effects on gross morphology and histological characteristics of transplants. The integrity of alginate of transplants increased as the in vitro culture period increased. Transplants were characterized by an opaque and yellowish color, fair burnish, a firm to elastic texture, but without any evidence of calcification spots. Histological findings agreed with the clinical determination of hyaline cartilage, characterized by isolated cells with basophilic ground substance positive in Safranin-O staining and collagen type II immunohistochemistry. Transplants with exposure to TGF-beta1 for more than 2 weeks before transplantation, lost burnish, were flexible in texture, and had an increased formation of calcification spots. Accordingly, 1-week exposure to TGF-beta1 in vitro before transplantation is appropriate for neocartilage formation of human MSCs in alginate. These findings suggested that regeneration using cell therapy or tissue engineering should assist in ascertaining the optimal timing of transplantation.


Subject(s)
Alginates , Cartilage/physiology , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/physiology , Animals , Cartilage/cytology , Cells, Cultured , Glucuronic Acid , Hexuronic Acids , Humans , Immunohistochemistry , Male , Mice , Mice, Nude , Neovascularization, Physiologic , Time Factors , Transplantation, Heterologous
12.
Stem Cells ; 22(7): 1321-9, 2004.
Article in English | MEDLINE | ID: mdl-15579649

ABSTRACT

Previous reports debated the effects of differentiation on adenoviral vector (AdV) transduction efficiency and Coxsackie-adenovirus receptor (CAR) expression. This prompted us to investigate the efficiency of AdV transduction and CAR expression in human mesenchymal stem cells (hMSCs) and their differentiated progeny. Current results revealed high efficiency (>90%) of AdV transduction and a consistent level of CAR expression in hMSCs by the use of AdV carrying the enhanced green fluorescent protein reporter gene. Competition of CAR with blocking monoclonal antibody RmcB resulted in a reduction in transduction efficiency, indicating the CAR involvement in transduction of hMSCs. The cells were then induced to differentiate into bone, fat, or neural cells, and results demonstrated that the differentiation was accompanied with a consistent decline in AdV transduction and a decrement in CAR expression. Cells were infected with AdV and then induced into differentiation, and results demonstrated that transduced cells preserved differentiation potentials and still had transgene expression in a subpopulation of cells for 4 weeks and even in tested lineage-specific differentiation. According to the present investigation, undifferentiated hMSCs can serve as a gene-delivering system, and gene transfer into hMSCs before differentiation can resolve the difficulties in transduction of their differentiated progeny.


Subject(s)
Adenoviridae/genetics , Gene Transfer Techniques , Mesenchymal Stem Cells/cytology , Receptors, Virus/biosynthesis , Adipocytes/cytology , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/metabolism , Binding, Competitive , Bone Marrow Cells/cytology , Cell Differentiation , Cell Line , Cell Lineage , Coxsackie and Adenovirus Receptor-Like Membrane Protein , Genes, Reporter/genetics , Genetic Vectors , Green Fluorescent Proteins/chemistry , Green Fluorescent Proteins/metabolism , HeLa Cells , Humans , Microscopy, Fluorescence , Neurons/cytology , Signal Transduction , Transgenes
13.
Gene ; 340(1): 141-50, 2004 Sep 29.
Article in English | MEDLINE | ID: mdl-15556302

ABSTRACT

Bone marrow-derived human mesenchymal stem cells (hMSCs) give rise to adipocytes in response to a medium containing dexamethasone, isobutylmethylxanthine, and insulin. A cDNA microarray was applied to analyze the gene expression profiles between the cells at day 0 and at day 3 of incubation in the adipogenic medium, when the cells began to express PPARgamma2, a transcription factor of adipogenesis. Several genes that were regulated during this time period were then confirmed by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Interestingly, several genes identified previously as markers of lineage-specific differentiations other than adipocyte were regulated during adipogenesis. We totally identified 82 genes that were differentially induced by fivefold or greater, and 31 genes that were differentially suppressed by twofold or more. Among them, 55 genes were not previously examined to associate with adipogenesis or have not been determined in hMSCs, therefore, these data provide novel information on the genes involved in adipogenesis of hMSCs.


Subject(s)
Adipocytes/metabolism , Cell Differentiation/genetics , Gene Expression Profiling , Mesenchymal Stem Cells/metabolism , 1-Methyl-3-isobutylxanthine/pharmacology , Adipocytes/cytology , Cells, Cultured , Dexamethasone/pharmacology , Gene Expression Regulation/drug effects , Humans , Insulin/pharmacology , Mesenchymal Stem Cells/cytology , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction
14.
Int J Cancer ; 110(3): 313-9, 2004 Jun 20.
Article in English | MEDLINE | ID: mdl-15095294

ABSTRACT

hMSCs derived from bone marrow are useful as a species-specific cell culture system for studying cell lineage differentiation and tissue remodeling. However, hMSCs usually have a short in vitro life span due to replicative senescence. We therefore used a high dose of retroviral vector LXSN-16E6E7 to transduce hMSCs of an aging donor and obtained an actively proliferating cell line, designated KP-hMSCs, which expressed HPV16 E6/E7 mRNA. Whereas parental hMSCs ceased to grow after 30 PDs, KP-hMSCs could be propagated beyond 100 PDs. With culture procedures to avoid selection pressure and crowded cell growth, KP-hMSCs showed no signs of neoplastic transformation as examined by soft-agar anchorage-independent growth and NOD-SCID mouse tumorigenicity assays. KP-hMSCs gave similar cytofluorimetric profiles of 31 CD markers to those of the parental primary hMSCs, except with some morphologic changes and expansion of an originally very minor CD34(dim)CD38(+)CD50+ cell population. Upon exposure to specific stimulating conditions in vitro, KP-hMSCs could respond and differentiate along the mesenchymal (bone, fat and cartilage) and nonmesenchymal (neuron) cell lineages. Our results indicated that hMSCs could be immortalized by transduction with HPV16 E6/E7, maintained without neoplastic transformation by careful culture procedures and thus useful for stem cell research and clinical application.


Subject(s)
Cell Transformation, Neoplastic , Genetic Therapy/methods , Mesoderm/cytology , Oncogene Proteins, Viral/genetics , Repressor Proteins , Stem Cells/cytology , ADP-ribosyl Cyclase/biosynthesis , ADP-ribosyl Cyclase 1 , Animals , Antigens, CD/biosynthesis , Antigens, CD34/biosynthesis , Cell Adhesion Molecules , Cell Differentiation , Cell Division , Cell Line , Cell Lineage , Female , Flow Cytometry , Humans , Membrane Glycoproteins , Mice , Mice, SCID , Microscopy, Fluorescence , Middle Aged , Papillomavirus E7 Proteins , Phenotype , RNA, Messenger/metabolism , Retroviridae/genetics , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Time Factors
15.
Childs Nerv Syst ; 19(10-11): 744-9, 2003 Nov.
Article in English | MEDLINE | ID: mdl-13680293

ABSTRACT

OBJECTIVES: One of the fundamental aspects of nitric oxide (NO) is the regulation of the inflammatory processes involved in neuronal apoptosis. Expressions of NO and NO synthase (NOS) are considered to be involved in brain tissue injuries and brain tumors. The purpose of our study was to investigate the roles of NO and inducible-form NOS (iNOS) in the pathogenesis of brain tumors. METHODS: NO levels in the cerebrospinal fluid (CSF) of 36 brain tumor patients were detected utilizing the NO-chemiluminescence method. Deparaffinized tissue sections were immunostained for the presence of antibodies against iNOS and for apoptosis using the TUNEL stain. The results were compared with 10 control patients (with epilepsy and hydrocephalus). CONCLUSIONS: Higher levels of NO and iNOS activities may induce immune responses and neurotoxicities. This preliminary study revealed elevated NO and NOS activities with an increased amount of apoptotic processes in brain tumor tissues, which may indicate the possible roles of NO in the formation of brain tumors.


Subject(s)
Brain Neoplasms/cerebrospinal fluid , Nitric Oxide/cerebrospinal fluid , Adolescent , Adult , Apoptosis , Brain Neoplasms/classification , Brain Neoplasms/complications , Brain Neoplasms/enzymology , Child , Child, Preschool , Epilepsy/cerebrospinal fluid , Epilepsy/etiology , Female , Humans , Hydrocephalus/cerebrospinal fluid , Hydrocephalus/etiology , Immunohistochemistry , In Situ Nick-End Labeling , Infant , Male , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II
16.
Ophthalmologica ; 217(5): 342-6, 2003.
Article in English | MEDLINE | ID: mdl-12913324

ABSTRACT

Abnormal nitric oxide (NO) synthesis has been implicated in the pathogenesis of diabetes mellitus. The aim of our study was to elucidate the relationship between the stages of diabetic retinopathy (DR) and the NO levels in aqueous humor and plasma. Using the chemiluminescence assay, we measured the concentrations of NO in aqueous humor and plasma samples obtained during intraocular surgery from 45 diabetic patients and 19 nondiabetic cataract patients. The patients with diabetes were classified into 4 groups: proliferative DR (PDR) with active neovascularization (active PDR; 9 cases), PDR with quiescent neovascularization (regressed PDR; 6 cases), background DR (BDR; 16 cases) and no DR (14 cases). We found that the aqueous NO levels (mean +/- SE) of the active PDR group (83.2 +/- 13.9 microM) were significantly higher than those of the BDR group (45.8 +/- 6.0 microM, p = 0.049) and the diabetics without DR (33.3 +/- 5.2 microM, p = 0.011), and, although not statistically significantly, they were also higher than those of the regressed PDR group (52.1 +/- 10.3 microM, p = 0.224). However, no significant differences were observed between any of the diabetic subgroups in the plasma NO levels (p = 0.345). We therefore concluded that NO present in the ocular tissues may play important roles in the progression of DR.


Subject(s)
Diabetic Retinopathy/metabolism , Nitric Oxide/metabolism , Retinal Neovascularization/metabolism , Aged , Aqueous Humor/metabolism , Cataract/metabolism , Diabetic Retinopathy/physiopathology , Disease Progression , Humans , Luminescent Measurements , Middle Aged , Retinal Neovascularization/physiopathology
17.
Ophthalmologica ; 217(4): 298-301, 2003.
Article in English | MEDLINE | ID: mdl-12792138

ABSTRACT

Human cytomegalovirus (HCMV) retinitis is the most common ocular opportunistic infection in AIDS. It often leads to blindness if left untreated. The questions as to how HCMV infection causes retinal immunopathogenesis and visual destruction in AIDS patients have not been completely established. Here we reported that the nitric oxide (NO) levels in aqueous humor samples in 10 AIDS patients with CMV retinitis (104.3 +/- 27.1 microM) were higher than the levels in 7 AIDS patients without CMV retinitis (36.1 +/- 10.4 micro M; p < 0.001). After ganciclovir treatment, the NO level in the vitreous body of 5 patients declined dramatically (53.4 +/- 11.8 micro M). By using immunohistochemistry assay, we found that the aggregates of macrophages infiltrated in the CMV-infected retina of 4 AIDS patients. Moreover, the expression of inducible-form NO synthase was detected in the infected retina of these patients. These results suggest that NO production in the eye may play a fundamental role in the immunopathogenesis of AIDS patients with CMV retinitis.


Subject(s)
Acquired Immunodeficiency Syndrome/complications , Acquired Immunodeficiency Syndrome/metabolism , Aqueous Humor/metabolism , Cytomegalovirus Infections/complications , Nitric Oxide/metabolism , Retinitis/virology , Antiviral Agents/therapeutic use , Cell Aggregation , Cytomegalovirus Infections/drug therapy , Ganciclovir/therapeutic use , Humans , Immunohistochemistry , Luminescent Measurements , Macrophages/enzymology , Macrophages/pathology , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Retinitis/enzymology , Retinitis/pathology
18.
Ophthalmologica ; 216(5): 346-50, 2002.
Article in English | MEDLINE | ID: mdl-12424401

ABSTRACT

Though several studies have shown that the biochemical function of nitric oxide (NO) in the eye might play an important role in the regulation of intraocular pressure (IOP), local control of ocular blood flow and loss of retinal ganglion cells by apoptosis, it is unclear whether the role of NO is similar in the pathogenesis of different kinds of glaucoma: primary open-angle glaucoma (POAG), chronic closed-angle glaucoma (CCAG) and neovascular glaucoma (NVG). To further explore this issue, we measured the concentrations of NO in aqueous humor and plasma samples from patients with POAG (n = 31), CCAG (n = 76), NVG (n = 8) and cataract (n = 30). All of the NVG patients suffered from severe proliferative diabetic retinopathy, while other patients were free of any other systemic disease. The NO levels in both aqueous humor and plasma samples were assessed by chemiluminescence assay. We found that the NO levels in aqueous humor samples were greatly varied in patients with POAG (36.2 +/- 3.3 microM), CCAG (47.7 +/- 3.4 microM) and NVG (65.8 +/- 5.4 microM), and all of them were significantly higher than in cataract patients (27.0 +/- 2.9 microM p < 0.05). Except NVG patients whose NO levels in plasma samples were highest (24.1 +/- 3.5 microM) among all groups, the plasma NO levels were not significantly different between the other glaucoma patients and the cataract patients. We therefore concluded that significant variation of the elevated NO levels in aqueous humor samples from the patients with different types of glaucoma may reflect their differences in the pathogenesis.


Subject(s)
Aqueous Humor/metabolism , Glaucoma, Angle-Closure/metabolism , Glaucoma, Neovascular/metabolism , Glaucoma, Open-Angle/metabolism , Nitric Oxide/metabolism , Aged , Cataract/metabolism , Female , Humans , Luminescent Measurements , Male , Middle Aged , Osmolar Concentration
19.
Phys Ther ; 82(6): 544-56, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12036396

ABSTRACT

BACKGROUND AND PURPOSE: Translational mobilization techniques are frequently used by physical therapists as an intervention for patients with limited ranges of motion (ROMs). However, concrete experimental support for such practice is lacking. The purpose of the study was to evaluate the effect of simulated dorsal and ventral translational mobilization (DTM and VTM) of the glenohumeral joint on abduction and rotational ROMs. METHODS: Fourteen fresh frozen shoulder specimens from 5 men and 3 women (mean age=77.3 years, SD=10.1, range=62-91) were used for this study. Each specimen underwent 5 repetitions of DTM and VTM in the plane of scapula simulated by a material testing system (MTS) in the resting position (40 of abduction in neutral rotation) and at the end range of abduction with 100 N of force. Abduction and rotation were assessed as the main outcome measures before and after each mobilization procedure performed and monitored by the MTS (abduction, 4 N m) and by a servomotor attached to the piston of the actuator of the MTS (medial and lateral rotation, 2 N m). RESULTS: There were increases in abduction ROM for both DTM (mean=2.10 , SD=1.76 ) and VTM (mean=2.06 , SD=1.96 ) at the end-range position. No changes were found in the resting position following the same procedure. Small increases were also found in lateral rotation ROM after VTM in the resting position (mean=0.90 , SD=0.92 , t=3.65, P=.003) and in medial rotation ROM after DTM (mean=0.97 , SD=1.45 , t=2.51, P=.026) at the end range of abduction. DISCUSSION AND CONCLUSION: The results indicate that both DTM and VTM procedures applied at the end range of abduction improved glenohumeral abduction range of motion. Whether these changes would result in improved function could not be determined because of the use of a cadaver model.


Subject(s)
Shoulder Joint/physiology , Aged , Aged, 80 and over , Analysis of Variance , Biomechanical Phenomena , Cadaver , Female , Humans , In Vitro Techniques , Male , Range of Motion, Articular
20.
Arch Phys Med Rehabil ; 83(3): 360-6, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11887117

ABSTRACT

OBJECTIVES: To quantify forces applied by therapists during dorsal glide translational mobilization of the glenohumeral joint, to determine the relationship of tissue resistance to the load-displacement relation of the glenohumeral joint, and to determine the safety of the forces applied by the therapists during dorsal glide translational mobilization. DESIGN: A fresh cadaver shoulder specimen mounted on a 6-axis load cell was used to register forces applied by therapists during dorsal glide translational mobilization of the glenohumeral joint in a test-retest pattern. SETTING: Biomechanics laboratory. PARTICIPANTS: Twelve experienced orthopedic physical therapists. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Forces exerted by therapists during passive dorsal glide translational mobilization in the loose-packed position and in the end range of abduction, with different grades of movements. The movements did not include any manipulation or thrust-type procedures. Simulated dorsal glide procedures were performed by the material testing system to construct the load-displacement curve of the glenohumeral specimen. The corresponding locations of the forces applied by therapists were interpolated and plotted on the load-displacement curve. RESULTS: The peak force values measured during mobilization were characterized by large intertherapist variability: coefficients of variation ranged from 40.97% to 77.49%. Test-retest reliability for intrasession measures was high (ICC(2,1) range,.90-.94); intersession reliability was poor (ICC(2,1) range,.01-.54). The mean forces ranged from 18.36 to 38.76N. When interpolated to the load-displacement curve, the mean peak forces obtained fell mostly in the toe and the linear elastic regions of the load-displacement curve. CONCLUSION: Force parameters measured during dorsal glide mobilization were characterized by large intertherapist variability with high intrasession and poor intersession test-retest reliability. The mobilization forces applied by experienced orthopedic physical therapists fall safely in the toe and the linear elastic regions of the load-displacement curve.


Subject(s)
Physical Therapy Specialty , Shoulder Joint/physiology , Adult , Biomechanical Phenomena , Female , Humans , Male , Middle Aged , Movement/physiology , Pressure , Range of Motion, Articular
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