AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential mechanism.METHODS:The HRECs were divided into four groups:normal glucos...AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential mechanism.METHODS:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A group.The cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular behaviour.Real-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both P<0.05).Vialinin A also inhibited highglucose-induced tube formation of HRECs.The expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(P<0.05).CONCLUSION:Vialinin A inhibits the cell viability of HRECs.It may serve as a potential target for anti-angiogenic therapy.展开更多
AIM:To observe the effect of human umbilical cord mesenchymal stem cells(hUCMSCs)secretions on the relevant factors in mouse retinal astrocytes,and to investigate the effect of hUCMSCs on the expression of vascular en...AIM:To observe the effect of human umbilical cord mesenchymal stem cells(hUCMSCs)secretions on the relevant factors in mouse retinal astrocytes,and to investigate the effect of hUCMSCs on the expression of vascular endothelial growth factor-A(VEGF-A)and to observe the therapeutic effect on the mouse model of retinopathy of prematurity(ROP).METHODS:Cultured hUCMSCs and extracted exosomes from them and then retinal astrocytes were divided into control group and hypoxia group.MTT assay,flow cytometry,reverse transcription-polymerase chain reaction(RT-PCR)and Western blot were used to detect related indicators.Possible mechanisms by which hUCMSCs exosomes affect VEGF-A expression in hypoxia-induced mouse retinal astrocytes were explored.At last,the efficacy of exosomes of UCMSCs in a mouse ROP model was explored.Graphpad6 was used to comprehensively process data information.RESULTS:The secretion was successfully extracted from the culture supernatant of hUCMSCs by gradient ultracentrifugation.Reactive oxygen species(ROS)and hypoxia inducible factor-1α(HIF-1α)of mice retinal astrocytes under different hypoxia time and the expression level of VEGF-A protein and VEGF-A mRNA increased,and the ROP cell model was established after 6h of hypoxia.The secretions of medium and high concentrations of hUCMSCs can reduce ROS and HIF-1α,the expression levels of VEGF-A protein and VEGF-A mRNA are statistically significant and concentration dependent.Compared with the ROP cell model group,the expression of phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)signal pathway related factors in the hUCMSCs exocrine group is significantly decreased.The intravitreal injection of the secretions of medium and high concentrations of hUCMSCs can reduce VEGF-A and HIF-1αin ROP model tissues.HE staining shows that the number of retinal neovascularization in ROP mice decreases with the increase of the dose of hUCMSCs secretion.CONCLUSION:In a hypoxia induced mouse retinal astrocyte model,hUCMSCs exosomes are found to effectively reduce the expression of HIF-1αand VEGF-A,which are positively correlated with the concentration of hUCMSCs exosomes.HUCMSCs exosomes can effectively reduce the number of retinal neovascularization and the expression of HIF-1αand VEGF-A proteins in ROP mice,and are positively correlated with drug dosage.Besides,they can reduce the related factors on the PI3K/AKT/mTOR signaling pathway.展开更多
AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the...AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the retinal tissue in diabetic rats.METHODS:The expression of HDAC7 in HRMECs under high glucose and the retinal tissue from normal or diabetic rats were detected with immunohistochemistry and Western blot.LV-shHDAC7 HRMECs were used to study the effect of HDAC7 on cell activities.Cell count kit-8(CCK-8),5-ethynyl2’-deoxyuridine(EdU),flow cytometry,scratch test,Transwell test and tube formation assay were used to examine the ability of cell proliferation,migration,and angiogenesis.Finally,a preliminary exploration of its mechanism was performed by Western blot.RESULTS:The expression of HDAC7 was both upregulated in retinal tissues of diabetic rats and high glucosetreated HRMECs.Down-regulation of HDAC7 expression significantly reduced the ability of proliferation,migration,and tube formation,and reversed the high glucose-induced high expression of CDK1/Cyclin B1 and vascular endothelial growth factor in high glucose-treated HRMECs.CONCLUSION:High glucose can up-regulate the expression of HDAC7 in HRMECs.Down-regulation of HDAC7 can inhibit HRMECs activities.HDAC7 is proposed to be involved in pathogenesis of diabetic retinopathy and a therapeutic target.展开更多
AIM:To investigate the effects of luteolin on apoptosis,the cell cycle,and the expression and secretion of vascular endothelial growth factor(VEGF)in human choroidal melanoma cells(C918 and OCM-1).METHODS:C918 and OCM...AIM:To investigate the effects of luteolin on apoptosis,the cell cycle,and the expression and secretion of vascular endothelial growth factor(VEGF)in human choroidal melanoma cells(C918 and OCM-1).METHODS:C918 and OCM-1 cells cultured in vitro were treated with various concentrations of luteolin(0,5,10,15μmol/L).Cell growth was observed with an inverted microscope,and cell cycle arrest was detected by propidium iodide(PI)staining using flow cytometry.Apoptosis was detected by Hoechst33342 staining,and apoptosis rate was determined by Annexin V-FITC/PI experiments using flow cytometry.The expression of apoptosis-related proteins Bcl-2,Bax and VEGF was analyzed using Western blots.The levels of VEGF secreted by the cells into the supernatant was analyzed using ELISA.RESULTS:After treating with 5 to 15μmol/L luteolin for 48 h,the fusion degree of C918 and OCM-1 cells decreased,and more floating apoptotic cells appeared.Luteolin treatment increased the G0-G1 phase ratio of the C918 and OCM-1 cells,blocked cell cycle progression,and increased the apoptosis rate of the C918 and OCM-1 cells.Western blot showed that luteolin decreased the expression of Bcl-2 and VEGF in the C918 and OCM-1 cells and increased the expression of Bax protein.The ELISA results showed that 10 to 15μmol/L luteolin decreased the cell secretion of VEGF.CONCLUSION:Luteolin may induce apoptosis by regulating the levels of apoptosis-related proteins in C918 and OCM-1 cells.Luteolin can induce cell cycle arrest,decrease the expression of VEGF.展开更多
AIM: To integrally understand the effects of human vascular endothelial cells(VECs) on the proliferation of vascular smooth muscle cells(VSMCs).METHODS: Various kinds of human VECs of different origins were co-culture...AIM: To integrally understand the effects of human vascular endothelial cells(VECs) on the proliferation of vascular smooth muscle cells(VSMCs).METHODS: Various kinds of human VECs of different origins were co-cultured with human aortic smooth muscle cells, a representative of human VSMCs. To exclude the irrelevant effects due to growth competition between VECs and VSMCs, the proliferation of VECs had previously been arrested via a low-dose gamma rayirradiation. To discriminately analyze the proliferation of VSMCs from that of VECs, the former cells were labeled with red fluorescent dye while the latter cells were labeled with green fluorescent dye before performing coculture experiments. After 4 d, total cells were harvested and subjected to flow cytometric analyses. Decrements in red fluorescence intensities due to proliferationmediated dilutions were measured and mathematically processed using a specific software to quantitatively evaluate the proliferation of VSMCs. The findings obtained from the flow cytometry-based analyses were further validated by microscopic observations. RESULTS: Commercially available primary cultured human VECs exclusively promoted VSMC proliferation regardless of their tissue origins and we termed these pro-proliferative VECs as "typeⅠ". By contrast, VECs freshly generated from human bone marrow-derived endothelial progenitors cells or human pluripotent stem cells including embryonic stem cells and induced pluripotent stem cells suppressed VSMC proliferation and we termed these anti-proliferative VECs as "typeⅡ". Repetitive subcultures as well as oxidative stress induced "type Ⅱ VECs to typeⅠ" conversion along with an induction of Regulator of G-protein signaling 5(RGS5)Compatibly, anti-oxidant treatments suppressed both the subculture-dependent "typeⅡ to typeⅠ" conversion and an induction of RGS5 gene. Immunostaining studies of clinical specimens indicated that RGS5 protein expressions in endothelial layers were low in norma arteries but they were up-regulated in pathologica arteries including hypertension, atherosclerosis and autoimmune vasculitis in a dose-dependent manner Overexpression and knockdown of RGS5 caused that"typeⅡ to typeⅠ" and "typeⅠ to type Ⅱ" phenotype conversions of VECs, respectively. CONCLUSION: Human VECs are categorized into two types: pro-proliferative RGS5^(high) VECs(typeⅠ) and antiproliferative RGS5 ^(low) VECs(typeⅡ).展开更多
BACKGROUND: Vascular endothelial growth factor (VEGF) acts as "molecular bridge" following ischemic stroke to improve and restore blood supply and reduce infarction volume. Clinical studies have demonstrated the ...BACKGROUND: Vascular endothelial growth factor (VEGF) acts as "molecular bridge" following ischemic stroke to improve and restore blood supply and reduce infarction volume. Clinical studies have demonstrated the efficacy of Rhizoma Chuanxiong (Chuanxiong) in the treatment of ischemic cerebrovascular diseases. However, whether it promotes endogenous VEGF expression in ischemic stroke remains unknown. OBJECTIVE: To investigate the influence of Rhizoma Chuanxiong on VEGF production in vitro cultured human umbilical vein endothelial cells and on VEGF expression in ischemic cerebral tissues to explore its role in angiogenesis. DESIGN, TIME AND SETTING: In vitro basic comparison of traditional Chinese drug-containing serum pharmacology; in vivo randomized, controlled, animal experiment. This study was performed at the Medical Laboratory of West China Hospital, Sichuan University between December 2002 and April 2004. MATERIALS: Two Chinese rabbits were selected. One was intragastrically perfused with 5.8 g/kg Rhizoma Chuanxiong extract twice per day for three consecutive days to prepare Rhizoma Chuanxiong extract-containing serum. The remaining rabbit was intragastrically perfused with the same volume of normal saline twice per day for three consecutive days. Rhizoma Chuanxiong extract was provided by Beijing Traditional Chinese Medicine Research Institute, predominantly composed of ligustrazine, ligustilide, and ferulic acid. ChemiKineTM human VEGF Kit was purchased from Chemicon, USA; mouse anti-VEGF monoclonal antibody and biotin-goat anti-mouse IgG were purchased from Santa Cruz Biotechnology. Inc., USA. METHODS: (1) In vitro experiment: in vitro cultured human umbilical vein endothelial cells were separately incubated in rabbit serum with 10% Rhizoma Chuanxiong extract, normal medium without rabbit serum, and rabbit serum without Rhizoma Chuanxiong extract (blank control). In addition, cells from the three groups were incubated under normoxia (5% CO2, 95% air) and hypoxia (1% 02, 5% CO2, 94% N2), respectively, for 24 hours. (2) In vivo experiment: a total of 4/44 Sprague Dawley rats were selected for the sham-operated group (no occlusion), and the remaining rats were used to establish a cerebral ischemiaJreperfusion model by suture occlusion. 32 animals with ischemia/reperfusion injury were randomly divided into treatment and model groups, with 16 rats in each group. Both groups were intraperitoneally infused with 0.58 g/kg Rhizoma Chuanxiong extract and normal saline two hours following reperfusion. The sham-operated group was administrated normal saline. Animals were treated with saline or Chuanxiong extracts (0.58 g/kg) twice per day for three consecutive days. MAIN OUTCOME MEASURES: In vitro experiment: VEGF concentration was detected in each group by enzyme-linked immunosorbent assay. In vivo experiment: behavioral alterations of rats were evaluated by neurological function scale; infarct volume was assessed by hematoxylin-eosin staining; VEGF protein expression in the infarct regions was determined by immunohistochemistry. RESULTS: (1) VEGF levels were similar between the three groups under normexic condition (P 〉 0.05); while hypoxia induced VEGF production (P 〈 0.01 ). VEGF levels in the drug-containing serum group were particularly higher compared with the other groups (P 〈 0.01). (2) Compared with normal saline treatment, Rhizoma Chuanxiong extract significantly improved the neurological scale and reduced cerebral infarct volumes (P〈 0.05). The percent of VEGF-positive cells was significantly greater than the model group (P 〈 0.05). The sham-operated group exhibited normal neurological function, with no infarct focus. CONCLUSION: Rhizoma Chuanxiong extract-containing rabbit serum effectively promoted cultured VEGF production under hypoxia. Rhizoma Chuanxiong extract upregulated VEGF expression in the infarct region, improved neurological function, and reduced infarct size.展开更多
In the current landscape of endothelial cell isolation for building in vitro models of the blood-brain barrier,our work moves towards reproducing the features of the neurovascular unit to achieve glial compliance thro...In the current landscape of endothelial cell isolation for building in vitro models of the blood-brain barrier,our work moves towards reproducing the features of the neurovascular unit to achieve glial compliance through an innovative biomimetic coating technology for brain chronic implants.We hypothesized that the autologous origin of human brain mic rovascular endothelial cells(hBMECs)is the first requirement for the suitable coating to prevent the glial inflammato ry response trigge red by foreign neuroprosthetics.Therefo re,this study established a new procedure to preserve the in vitro viability of hBMECs isolated from gray and white matter specimens taken from neurosurge ry patients.Culturing adult hBMECs is generally considered a challenging task due to the difficult survival ex vivo and progressive reduction in proliferation of these cells.The addition of 10 nMβ-estradiol 17-acetate to the hBMEC culture medium was found to be an essential and discriminating factor promoting adhesion and proliferation both after isolation and thawing,suppo rting the well-known protective role played by estrogens on microvessels.In particular,β-estradiol 17-acetate was critical for both freshly isolated and thawed female-derived hBMECs,while it was not necessary for freshly isolated male-derived hBMECs;however,it did countera ct the decay in the viability of the latter after thawing.The tumo r-free hBMECs were thus cultured for up to 2 months and their growth efficiency was assessed befo re and after two periods of cryopreservation.Des pite the thermal stress,the hBMECs remained viable and suitable for re-freezing and storage for several months.This approach increasing in vitro viability of hBMECs opens new perspectives for the use of cryopreserved autologous hBMECs as biomimetic therapeutic tools,offering the potential to avoid additional surgical sampling for each patient.展开更多
AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing rec...AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P【0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P【0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P【0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P【0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.展开更多
AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cass...AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully constructed.After G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P【 0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells. CONCLUSION: Expression of antisense VEGF RNA in SMMC-7721 cells could decrease the tumorigenicity, and antisense-VEGF gene therapy may be an adjuvant treatment for hepatoma.展开更多
BACKGROUND: The highly specific vascular endothelialgrowth factor (VEGF) induces the growth of vascular en-dothelial cell. This study was to construct the eukaryoticexpression plasmid of vascular endothelial growth fa...BACKGROUND: The highly specific vascular endothelialgrowth factor (VEGF) induces the growth of vascular en-dothelial cell. This study was to construct the eukaryoticexpression plasmid of vascular endothelial growth factorl65(VEGF165) and observe its expression in vascular smoothmuscles (VSMCs).METHODS: The primers were designed and synthesizedaccording to the gene sequences of human VEGF165. TheVEGF165 gene was obtained from umbilic artery tissue bythe method of RT-PCR, then it was cloned to eukaryoticexpression plasmid pBudCE4.1 by recombination strategy.The eukaryotic expression plasmid named pBudCE4.1/VEGF165 was identified by restriction enzyme digestion,and was sequenced. The pBudCE4.1/VEGF165 was trans-fected into VSMCs by using lipofection. The VEGF165 ex-pression of mRNA and protein was detected by RT-PCRand Western blot respectively.RESULTS: VEGF165 was shown about 576bp by RT-PCR.Sequencing revealed the amplified VEGF165 gene was iden-tical with that in the GeneBank. Restrictive enzyme (HindBam HI) digestion analysis showed that recombinantexpression plasmid pBudCE4. l/tVEGF165 had been con-structed successfully. The expression of VEGF165 at mRNAand protein levels in the transformed VSMCs had beendemonstrated by RT-PCR and Western blot.CONCLUSIONS: The recombinant eukaryotic expressionplasmid pBudCE4.1/VEGF165 has been successfully con-structed and expressed in transformed VSMCs. The presentstudy has laid a foundation for VEGF165 gene therapy ofvascular stenosis in the transplant organ.展开更多
AIM:To verify in vivo relevance of the categorization of human vascular endothelial cells(VECs)into type-I(proproliferative)and type-II(anti-proliferative).METHODS:Endothelial layers of murine femoral arteries were re...AIM:To verify in vivo relevance of the categorization of human vascular endothelial cells(VECs)into type-I(proproliferative)and type-II(anti-proliferative).METHODS:Endothelial layers of murine femoral arteries were removed by wire injury(WI)operation,a common technique to induce arteriostenosis.Type-I and type-II VECs produced from human induced pluripotent stem cells(iPSCs),whose characters were previously determined by their effects on the proliferation of vascular smooth muscle cells in in vitro co-culture experiments,were mixed with Matrigel?Matrix.The mixtures were injected into subcutaneous spaces around WI-operated femoral arteries for the transplanted human iPSC-derived VECs(iPSdECs)to take a route to the luminal surface via vasa vasorum,a nutrient microvessel for larger arteries.Histologies of the femoral arteries were examined over time.The presence of human iPSdECs was checked by immunostaining studies using an antibody that specifically recognizes human VECs.Degrees of stenosis of the femoral arteries were calculated after three weeks.To determine the optimal experimental condition,xenotransplantation experiments were performed under various conditions using immunocompromised mice as well as immunocompetent mice with or without administration of immunosuppressants.RESULTS:Because immunocompromised mice showed unexpected resistance to WI-induced arteriostenosis,we performed xenotransplantation experiments using immunocompetent mice along with immunosuppressant administrations.After one week,luminal surfaces of the WI-operated arteries were completely covered by human iPSdECs,showing the efficacy of our novel transplantation technique.After three weeks,type-IiPSdECs-transplanted arteries underwent total stenosis,while type-II-iPSdECs-transplanted arteries remained intact.However,untransplanted arteries of immunosuppressant-treated mice also remained intact by unknown reasons.We found that transplanted human VECs had already been replaced by murine endothelial cells by this time,indicating that a transient existence of human type-II-iPSdECs on arterial luminal surfaces can sufficiently prevent the development of stenosis.Thus,we re-performed xenotransplantation experiments using immunocompetent mice without administrating immunosuppressants and found that arteriostenosis was accelerated or prevented by transplantation of type-I or type-II iPSdECs,respectively.Similar results were obtained from the experiments using human embryonic stem cell-derived VECs at early passages(i.e.,type-II)and late passages(i.e.,type-I).CONCLUSION:Pro-and anti-stenosis capacities of type-I and type-II human iPSdECs were verified,respectively,promising a therapeutic application of allogenic iPSdECs.展开更多
Purpose:To investigate the spatial and temporal regulation effect of vascular endothelial growth factor(VEGF)on human fetal choroid vascularization.Methods:The eyeballs of 54human fetuses from the 9th week to the40th ...Purpose:To investigate the spatial and temporal regulation effect of vascular endothelial growth factor(VEGF)on human fetal choroid vascularization.Methods:The eyeballs of 54human fetuses from the 9th week to the40th week due to accidental abortion were studied by immunohistochemically staining for the expression of VEGF and proliferation cell nuclear antigen(PCNA).Results:(1)The distribution of VEGF expression in the retinal pigment epithelium(RPE)decreased with the increase of age,the peak of which was between the 9th and 14th week,(2)PCNAimmunoreactivity was localized within choriocapillaris endothe-lium,THe expression level decreased alone with fetus age,In this period the chori-ocapillaris endothelium kept proliferation,differentiation.canalization and remodelled to form the choroid vessels.(3)Statistically significant correlations were shown between the expression of VEGF in the PRE and that of PCNAin choriocapillaris endothelium(r=0.933,P<0.01).Conclusion:VEGF expression in PRE was positively involved in modulating human fetal choroid vascularization.Eye Science2000;16:11-14.展开更多
Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous ...Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous metastasis.Methods We prepared the conditioned mediums of each cell so as to study the effect of the conditioned medium on itself or others by MTT colorimetry. The comprehensive effect of interactions between two cells was determined by stratified transfilter co culture or direct contact co culture.Results The conditioned medium of human gastric carcinoma cell can stimulate the proliferation of the human vascular endothelial cell, but the CM of HVEC can inhibit the growth of HGCC. Both kinds of cells can inhibit the growth of itself. The ultimate comprehensive effect of the interactions between two kinds of cells was increase of total cell numbers.Conclusion There exist the complicated interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the tumor angiogenesis and the tumor hematogenous metastasis. The ultimate comprehensive effect of the interactions is increase of total cells numbers and tumor volume.展开更多
In the present study, human umbilical cord blood mesenchymal stem cells were injected into a rat model of traumatic brain injury via the tail vein. Results showed that 5-bromodeoxyuridine-labeled cells aggregated arou...In the present study, human umbilical cord blood mesenchymal stem cells were injected into a rat model of traumatic brain injury via the tail vein. Results showed that 5-bromodeoxyuridine-labeled cells aggregated around the injury site, surviving up to 4 weeks post-transplantation. In addition, transplantation-related death did not occur, and neurological functions significantly improved. Histological detection revealed attenuated pathological injury in rat brain tissues following human umbilical cord blood mesenchymal stem cell transplantation. In addition, the number of apoptotic cells decreased. Immunohistochemistry and in situ hybridization showed increased expression of brain-derived neurotrophic factor, nerve growth factor, basic fibroblast growth factor, and vascular endothelial growth factor, along with increased microvessel density in surrounding areas of brain injury. Results demonstrated migration of transplanted human umbilical cord blood mesenchymal stem cells into the lesioned boundary zone of rats, as well as increased angiogenesis and expression of related neurotrophic factors in the lesioned boundary zone.展开更多
The effects of vascular endothelial growth factor (VEGF) on neural differentiation of human embryonic stem cells (hESCs) in vitro and the possible mechanism were observed. The hESCs lines, TJMU1 and TJMU2, were es...The effects of vascular endothelial growth factor (VEGF) on neural differentiation of human embryonic stem cells (hESCs) in vitro and the possible mechanism were observed. The hESCs lines, TJMU1 and TJMU2, were established and stored by our laboratory, hESCs differentiated into neuronal cells through embryonic body formation. In this induction process, hESCs were divided into three groups: group A, routine induction; group B, routine induction+10 ng/mL VEGF; group C, routine in- duction+10 ng/mL VEGF+10 ng/mL VEGFR2/Fc. OCT4, Nestin and GFAP in each group were de- tected by RT-PCR, and the cells expressing Nestin and GFAP were counted by immunofluorescence. The percentage of Nestin positive cells in group B was significantly higher than in groups A and C, while the percentage of GFAP positive cells in group B was significantly lower than in groups A and C (P〈0.01). There was no significant difference between groups A and C (P〉0.05). It was concluded that VEGF, via VEGFR2, stimulated the neural differentiation of hESCs in vitro.展开更多
基金Supported by the National Natural Science Foundation of China(No.81970830)Jiangsu Provincial Medical Innovation Team(No.CXTDA2017039).
文摘AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential mechanism.METHODS:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A group.The cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular behaviour.Real-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both P<0.05).Vialinin A also inhibited highglucose-induced tube formation of HRECs.The expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(P<0.05).CONCLUSION:Vialinin A inhibits the cell viability of HRECs.It may serve as a potential target for anti-angiogenic therapy.
基金Supported by Tianjin Key Medical Discipline Specialty Construction Project(No.TJXZDXK-016A)Science Foundation of Tianjin Eye Hospital(No.YKZD1901).
文摘AIM:To observe the effect of human umbilical cord mesenchymal stem cells(hUCMSCs)secretions on the relevant factors in mouse retinal astrocytes,and to investigate the effect of hUCMSCs on the expression of vascular endothelial growth factor-A(VEGF-A)and to observe the therapeutic effect on the mouse model of retinopathy of prematurity(ROP).METHODS:Cultured hUCMSCs and extracted exosomes from them and then retinal astrocytes were divided into control group and hypoxia group.MTT assay,flow cytometry,reverse transcription-polymerase chain reaction(RT-PCR)and Western blot were used to detect related indicators.Possible mechanisms by which hUCMSCs exosomes affect VEGF-A expression in hypoxia-induced mouse retinal astrocytes were explored.At last,the efficacy of exosomes of UCMSCs in a mouse ROP model was explored.Graphpad6 was used to comprehensively process data information.RESULTS:The secretion was successfully extracted from the culture supernatant of hUCMSCs by gradient ultracentrifugation.Reactive oxygen species(ROS)and hypoxia inducible factor-1α(HIF-1α)of mice retinal astrocytes under different hypoxia time and the expression level of VEGF-A protein and VEGF-A mRNA increased,and the ROP cell model was established after 6h of hypoxia.The secretions of medium and high concentrations of hUCMSCs can reduce ROS and HIF-1α,the expression levels of VEGF-A protein and VEGF-A mRNA are statistically significant and concentration dependent.Compared with the ROP cell model group,the expression of phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)signal pathway related factors in the hUCMSCs exocrine group is significantly decreased.The intravitreal injection of the secretions of medium and high concentrations of hUCMSCs can reduce VEGF-A and HIF-1αin ROP model tissues.HE staining shows that the number of retinal neovascularization in ROP mice decreases with the increase of the dose of hUCMSCs secretion.CONCLUSION:In a hypoxia induced mouse retinal astrocyte model,hUCMSCs exosomes are found to effectively reduce the expression of HIF-1αand VEGF-A,which are positively correlated with the concentration of hUCMSCs exosomes.HUCMSCs exosomes can effectively reduce the number of retinal neovascularization and the expression of HIF-1αand VEGF-A proteins in ROP mice,and are positively correlated with drug dosage.Besides,they can reduce the related factors on the PI3K/AKT/mTOR signaling pathway.
基金Supported by the Shaanxi Province Traditional Chinese Medicine Project(No.SZY-KJCYC-2023-028)。
文摘AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the retinal tissue in diabetic rats.METHODS:The expression of HDAC7 in HRMECs under high glucose and the retinal tissue from normal or diabetic rats were detected with immunohistochemistry and Western blot.LV-shHDAC7 HRMECs were used to study the effect of HDAC7 on cell activities.Cell count kit-8(CCK-8),5-ethynyl2’-deoxyuridine(EdU),flow cytometry,scratch test,Transwell test and tube formation assay were used to examine the ability of cell proliferation,migration,and angiogenesis.Finally,a preliminary exploration of its mechanism was performed by Western blot.RESULTS:The expression of HDAC7 was both upregulated in retinal tissues of diabetic rats and high glucosetreated HRMECs.Down-regulation of HDAC7 expression significantly reduced the ability of proliferation,migration,and tube formation,and reversed the high glucose-induced high expression of CDK1/Cyclin B1 and vascular endothelial growth factor in high glucose-treated HRMECs.CONCLUSION:High glucose can up-regulate the expression of HDAC7 in HRMECs.Down-regulation of HDAC7 can inhibit HRMECs activities.HDAC7 is proposed to be involved in pathogenesis of diabetic retinopathy and a therapeutic target.
文摘AIM:To investigate the effects of luteolin on apoptosis,the cell cycle,and the expression and secretion of vascular endothelial growth factor(VEGF)in human choroidal melanoma cells(C918 and OCM-1).METHODS:C918 and OCM-1 cells cultured in vitro were treated with various concentrations of luteolin(0,5,10,15μmol/L).Cell growth was observed with an inverted microscope,and cell cycle arrest was detected by propidium iodide(PI)staining using flow cytometry.Apoptosis was detected by Hoechst33342 staining,and apoptosis rate was determined by Annexin V-FITC/PI experiments using flow cytometry.The expression of apoptosis-related proteins Bcl-2,Bax and VEGF was analyzed using Western blots.The levels of VEGF secreted by the cells into the supernatant was analyzed using ELISA.RESULTS:After treating with 5 to 15μmol/L luteolin for 48 h,the fusion degree of C918 and OCM-1 cells decreased,and more floating apoptotic cells appeared.Luteolin treatment increased the G0-G1 phase ratio of the C918 and OCM-1 cells,blocked cell cycle progression,and increased the apoptosis rate of the C918 and OCM-1 cells.Western blot showed that luteolin decreased the expression of Bcl-2 and VEGF in the C918 and OCM-1 cells and increased the expression of Bax protein.The ELISA results showed that 10 to 15μmol/L luteolin decreased the cell secretion of VEGF.CONCLUSION:Luteolin may induce apoptosis by regulating the levels of apoptosis-related proteins in C918 and OCM-1 cells.Luteolin can induce cell cycle arrest,decrease the expression of VEGF.
基金Supported by A Grant-in-Aid from the Ministry of HealthLabour and Welfare of Japan(KHD1017)a Grant-in-Aid from JST and PRESTO
文摘AIM: To integrally understand the effects of human vascular endothelial cells(VECs) on the proliferation of vascular smooth muscle cells(VSMCs).METHODS: Various kinds of human VECs of different origins were co-cultured with human aortic smooth muscle cells, a representative of human VSMCs. To exclude the irrelevant effects due to growth competition between VECs and VSMCs, the proliferation of VECs had previously been arrested via a low-dose gamma rayirradiation. To discriminately analyze the proliferation of VSMCs from that of VECs, the former cells were labeled with red fluorescent dye while the latter cells were labeled with green fluorescent dye before performing coculture experiments. After 4 d, total cells were harvested and subjected to flow cytometric analyses. Decrements in red fluorescence intensities due to proliferationmediated dilutions were measured and mathematically processed using a specific software to quantitatively evaluate the proliferation of VSMCs. The findings obtained from the flow cytometry-based analyses were further validated by microscopic observations. RESULTS: Commercially available primary cultured human VECs exclusively promoted VSMC proliferation regardless of their tissue origins and we termed these pro-proliferative VECs as "typeⅠ". By contrast, VECs freshly generated from human bone marrow-derived endothelial progenitors cells or human pluripotent stem cells including embryonic stem cells and induced pluripotent stem cells suppressed VSMC proliferation and we termed these anti-proliferative VECs as "typeⅡ". Repetitive subcultures as well as oxidative stress induced "type Ⅱ VECs to typeⅠ" conversion along with an induction of Regulator of G-protein signaling 5(RGS5)Compatibly, anti-oxidant treatments suppressed both the subculture-dependent "typeⅡ to typeⅠ" conversion and an induction of RGS5 gene. Immunostaining studies of clinical specimens indicated that RGS5 protein expressions in endothelial layers were low in norma arteries but they were up-regulated in pathologica arteries including hypertension, atherosclerosis and autoimmune vasculitis in a dose-dependent manner Overexpression and knockdown of RGS5 caused that"typeⅡ to typeⅠ" and "typeⅠ to type Ⅱ" phenotype conversions of VECs, respectively. CONCLUSION: Human VECs are categorized into two types: pro-proliferative RGS5^(high) VECs(typeⅠ) and antiproliferative RGS5 ^(low) VECs(typeⅡ).
基金the Major State Basic Research Development Program of China,No.G1999054402
文摘BACKGROUND: Vascular endothelial growth factor (VEGF) acts as "molecular bridge" following ischemic stroke to improve and restore blood supply and reduce infarction volume. Clinical studies have demonstrated the efficacy of Rhizoma Chuanxiong (Chuanxiong) in the treatment of ischemic cerebrovascular diseases. However, whether it promotes endogenous VEGF expression in ischemic stroke remains unknown. OBJECTIVE: To investigate the influence of Rhizoma Chuanxiong on VEGF production in vitro cultured human umbilical vein endothelial cells and on VEGF expression in ischemic cerebral tissues to explore its role in angiogenesis. DESIGN, TIME AND SETTING: In vitro basic comparison of traditional Chinese drug-containing serum pharmacology; in vivo randomized, controlled, animal experiment. This study was performed at the Medical Laboratory of West China Hospital, Sichuan University between December 2002 and April 2004. MATERIALS: Two Chinese rabbits were selected. One was intragastrically perfused with 5.8 g/kg Rhizoma Chuanxiong extract twice per day for three consecutive days to prepare Rhizoma Chuanxiong extract-containing serum. The remaining rabbit was intragastrically perfused with the same volume of normal saline twice per day for three consecutive days. Rhizoma Chuanxiong extract was provided by Beijing Traditional Chinese Medicine Research Institute, predominantly composed of ligustrazine, ligustilide, and ferulic acid. ChemiKineTM human VEGF Kit was purchased from Chemicon, USA; mouse anti-VEGF monoclonal antibody and biotin-goat anti-mouse IgG were purchased from Santa Cruz Biotechnology. Inc., USA. METHODS: (1) In vitro experiment: in vitro cultured human umbilical vein endothelial cells were separately incubated in rabbit serum with 10% Rhizoma Chuanxiong extract, normal medium without rabbit serum, and rabbit serum without Rhizoma Chuanxiong extract (blank control). In addition, cells from the three groups were incubated under normoxia (5% CO2, 95% air) and hypoxia (1% 02, 5% CO2, 94% N2), respectively, for 24 hours. (2) In vivo experiment: a total of 4/44 Sprague Dawley rats were selected for the sham-operated group (no occlusion), and the remaining rats were used to establish a cerebral ischemiaJreperfusion model by suture occlusion. 32 animals with ischemia/reperfusion injury were randomly divided into treatment and model groups, with 16 rats in each group. Both groups were intraperitoneally infused with 0.58 g/kg Rhizoma Chuanxiong extract and normal saline two hours following reperfusion. The sham-operated group was administrated normal saline. Animals were treated with saline or Chuanxiong extracts (0.58 g/kg) twice per day for three consecutive days. MAIN OUTCOME MEASURES: In vitro experiment: VEGF concentration was detected in each group by enzyme-linked immunosorbent assay. In vivo experiment: behavioral alterations of rats were evaluated by neurological function scale; infarct volume was assessed by hematoxylin-eosin staining; VEGF protein expression in the infarct regions was determined by immunohistochemistry. RESULTS: (1) VEGF levels were similar between the three groups under normexic condition (P 〉 0.05); while hypoxia induced VEGF production (P 〈 0.01 ). VEGF levels in the drug-containing serum group were particularly higher compared with the other groups (P 〈 0.01). (2) Compared with normal saline treatment, Rhizoma Chuanxiong extract significantly improved the neurological scale and reduced cerebral infarct volumes (P〈 0.05). The percent of VEGF-positive cells was significantly greater than the model group (P 〈 0.05). The sham-operated group exhibited normal neurological function, with no infarct focus. CONCLUSION: Rhizoma Chuanxiong extract-containing rabbit serum effectively promoted cultured VEGF production under hypoxia. Rhizoma Chuanxiong extract upregulated VEGF expression in the infarct region, improved neurological function, and reduced infarct size.
基金supported by EnTimeMent H2020-FETPROACT-824160(to LF)。
文摘In the current landscape of endothelial cell isolation for building in vitro models of the blood-brain barrier,our work moves towards reproducing the features of the neurovascular unit to achieve glial compliance through an innovative biomimetic coating technology for brain chronic implants.We hypothesized that the autologous origin of human brain mic rovascular endothelial cells(hBMECs)is the first requirement for the suitable coating to prevent the glial inflammato ry response trigge red by foreign neuroprosthetics.Therefo re,this study established a new procedure to preserve the in vitro viability of hBMECs isolated from gray and white matter specimens taken from neurosurge ry patients.Culturing adult hBMECs is generally considered a challenging task due to the difficult survival ex vivo and progressive reduction in proliferation of these cells.The addition of 10 nMβ-estradiol 17-acetate to the hBMEC culture medium was found to be an essential and discriminating factor promoting adhesion and proliferation both after isolation and thawing,suppo rting the well-known protective role played by estrogens on microvessels.In particular,β-estradiol 17-acetate was critical for both freshly isolated and thawed female-derived hBMECs,while it was not necessary for freshly isolated male-derived hBMECs;however,it did countera ct the decay in the viability of the latter after thawing.The tumo r-free hBMECs were thus cultured for up to 2 months and their growth efficiency was assessed befo re and after two periods of cryopreservation.Des pite the thermal stress,the hBMECs remained viable and suitable for re-freezing and storage for several months.This approach increasing in vitro viability of hBMECs opens new perspectives for the use of cryopreserved autologous hBMECs as biomimetic therapeutic tools,offering the potential to avoid additional surgical sampling for each patient.
文摘AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P【0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P【0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P【0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P【0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.
基金Project supported by National Natural Science Foundation of China,No.863 Z2001-04
文摘AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully constructed.After G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P【 0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells. CONCLUSION: Expression of antisense VEGF RNA in SMMC-7721 cells could decrease the tumorigenicity, and antisense-VEGF gene therapy may be an adjuvant treatment for hepatoma.
基金This study was supported by grants from the 973 National Basic ResearchProgram of China ( 2003CB515501 ) and the National Natural ScienceFoundation of China (No. 30270514).
文摘BACKGROUND: The highly specific vascular endothelialgrowth factor (VEGF) induces the growth of vascular en-dothelial cell. This study was to construct the eukaryoticexpression plasmid of vascular endothelial growth factorl65(VEGF165) and observe its expression in vascular smoothmuscles (VSMCs).METHODS: The primers were designed and synthesizedaccording to the gene sequences of human VEGF165. TheVEGF165 gene was obtained from umbilic artery tissue bythe method of RT-PCR, then it was cloned to eukaryoticexpression plasmid pBudCE4.1 by recombination strategy.The eukaryotic expression plasmid named pBudCE4.1/VEGF165 was identified by restriction enzyme digestion,and was sequenced. The pBudCE4.1/VEGF165 was trans-fected into VSMCs by using lipofection. The VEGF165 ex-pression of mRNA and protein was detected by RT-PCRand Western blot respectively.RESULTS: VEGF165 was shown about 576bp by RT-PCR.Sequencing revealed the amplified VEGF165 gene was iden-tical with that in the GeneBank. Restrictive enzyme (HindBam HI) digestion analysis showed that recombinantexpression plasmid pBudCE4. l/tVEGF165 had been con-structed successfully. The expression of VEGF165 at mRNAand protein levels in the transformed VSMCs had beendemonstrated by RT-PCR and Western blot.CONCLUSIONS: The recombinant eukaryotic expressionplasmid pBudCE4.1/VEGF165 has been successfully con-structed and expressed in transformed VSMCs. The presentstudy has laid a foundation for VEGF165 gene therapy ofvascular stenosis in the transplant organ.
基金Supported by Grant-in-Aid from the Ministry of HealthLabour and Welfare of Japan(KHD1017)+1 种基金by that from JSTPRESTO
文摘AIM:To verify in vivo relevance of the categorization of human vascular endothelial cells(VECs)into type-I(proproliferative)and type-II(anti-proliferative).METHODS:Endothelial layers of murine femoral arteries were removed by wire injury(WI)operation,a common technique to induce arteriostenosis.Type-I and type-II VECs produced from human induced pluripotent stem cells(iPSCs),whose characters were previously determined by their effects on the proliferation of vascular smooth muscle cells in in vitro co-culture experiments,were mixed with Matrigel?Matrix.The mixtures were injected into subcutaneous spaces around WI-operated femoral arteries for the transplanted human iPSC-derived VECs(iPSdECs)to take a route to the luminal surface via vasa vasorum,a nutrient microvessel for larger arteries.Histologies of the femoral arteries were examined over time.The presence of human iPSdECs was checked by immunostaining studies using an antibody that specifically recognizes human VECs.Degrees of stenosis of the femoral arteries were calculated after three weeks.To determine the optimal experimental condition,xenotransplantation experiments were performed under various conditions using immunocompromised mice as well as immunocompetent mice with or without administration of immunosuppressants.RESULTS:Because immunocompromised mice showed unexpected resistance to WI-induced arteriostenosis,we performed xenotransplantation experiments using immunocompetent mice along with immunosuppressant administrations.After one week,luminal surfaces of the WI-operated arteries were completely covered by human iPSdECs,showing the efficacy of our novel transplantation technique.After three weeks,type-IiPSdECs-transplanted arteries underwent total stenosis,while type-II-iPSdECs-transplanted arteries remained intact.However,untransplanted arteries of immunosuppressant-treated mice also remained intact by unknown reasons.We found that transplanted human VECs had already been replaced by murine endothelial cells by this time,indicating that a transient existence of human type-II-iPSdECs on arterial luminal surfaces can sufficiently prevent the development of stenosis.Thus,we re-performed xenotransplantation experiments using immunocompetent mice without administrating immunosuppressants and found that arteriostenosis was accelerated or prevented by transplantation of type-I or type-II iPSdECs,respectively.Similar results were obtained from the experiments using human embryonic stem cell-derived VECs at early passages(i.e.,type-II)and late passages(i.e.,type-I).CONCLUSION:Pro-and anti-stenosis capacities of type-I and type-II human iPSdECs were verified,respectively,promising a therapeutic application of allogenic iPSdECs.
文摘Purpose:To investigate the spatial and temporal regulation effect of vascular endothelial growth factor(VEGF)on human fetal choroid vascularization.Methods:The eyeballs of 54human fetuses from the 9th week to the40th week due to accidental abortion were studied by immunohistochemically staining for the expression of VEGF and proliferation cell nuclear antigen(PCNA).Results:(1)The distribution of VEGF expression in the retinal pigment epithelium(RPE)decreased with the increase of age,the peak of which was between the 9th and 14th week,(2)PCNAimmunoreactivity was localized within choriocapillaris endothe-lium,THe expression level decreased alone with fetus age,In this period the chori-ocapillaris endothelium kept proliferation,differentiation.canalization and remodelled to form the choroid vessels.(3)Statistically significant correlations were shown between the expression of VEGF in the PRE and that of PCNAin choriocapillaris endothelium(r=0.933,P<0.01).Conclusion:VEGF expression in PRE was positively involved in modulating human fetal choroid vascularization.Eye Science2000;16:11-14.
文摘Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous metastasis.Methods We prepared the conditioned mediums of each cell so as to study the effect of the conditioned medium on itself or others by MTT colorimetry. The comprehensive effect of interactions between two cells was determined by stratified transfilter co culture or direct contact co culture.Results The conditioned medium of human gastric carcinoma cell can stimulate the proliferation of the human vascular endothelial cell, but the CM of HVEC can inhibit the growth of HGCC. Both kinds of cells can inhibit the growth of itself. The ultimate comprehensive effect of the interactions between two kinds of cells was increase of total cell numbers.Conclusion There exist the complicated interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the tumor angiogenesis and the tumor hematogenous metastasis. The ultimate comprehensive effect of the interactions is increase of total cells numbers and tumor volume.
基金supported by Medical Scientific Research Program of Hebei Province in 2010, Hebei Provincial Health Department, No. 20100131
文摘In the present study, human umbilical cord blood mesenchymal stem cells were injected into a rat model of traumatic brain injury via the tail vein. Results showed that 5-bromodeoxyuridine-labeled cells aggregated around the injury site, surviving up to 4 weeks post-transplantation. In addition, transplantation-related death did not occur, and neurological functions significantly improved. Histological detection revealed attenuated pathological injury in rat brain tissues following human umbilical cord blood mesenchymal stem cell transplantation. In addition, the number of apoptotic cells decreased. Immunohistochemistry and in situ hybridization showed increased expression of brain-derived neurotrophic factor, nerve growth factor, basic fibroblast growth factor, and vascular endothelial growth factor, along with increased microvessel density in surrounding areas of brain injury. Results demonstrated migration of transplanted human umbilical cord blood mesenchymal stem cells into the lesioned boundary zone of rats, as well as increased angiogenesis and expression of related neurotrophic factors in the lesioned boundary zone.
文摘The effects of vascular endothelial growth factor (VEGF) on neural differentiation of human embryonic stem cells (hESCs) in vitro and the possible mechanism were observed. The hESCs lines, TJMU1 and TJMU2, were established and stored by our laboratory, hESCs differentiated into neuronal cells through embryonic body formation. In this induction process, hESCs were divided into three groups: group A, routine induction; group B, routine induction+10 ng/mL VEGF; group C, routine in- duction+10 ng/mL VEGF+10 ng/mL VEGFR2/Fc. OCT4, Nestin and GFAP in each group were de- tected by RT-PCR, and the cells expressing Nestin and GFAP were counted by immunofluorescence. The percentage of Nestin positive cells in group B was significantly higher than in groups A and C, while the percentage of GFAP positive cells in group B was significantly lower than in groups A and C (P〈0.01). There was no significant difference between groups A and C (P〉0.05). It was concluded that VEGF, via VEGFR2, stimulated the neural differentiation of hESCs in vitro.