BACKGROUND There are limited data on the use of glucose transport protein 1(GLUT-1)expre-ssion as a biomarker for predicting lymph node metastasis in patients with colorectal cancer.GLUT-1 and GLUT-3,hexokinase(HK)-II...BACKGROUND There are limited data on the use of glucose transport protein 1(GLUT-1)expre-ssion as a biomarker for predicting lymph node metastasis in patients with colorectal cancer.GLUT-1 and GLUT-3,hexokinase(HK)-II,and hypoxia-induced factor(HIF)-1 expressions may be useful biomarkers for detecting primary tumors and lymph node metastasis when combined with fluorodeoxyglucose(FDG)uptake on positron emission tomography/computed tomography(PET/CT).AIM To evaluate GLUT-1,GLUT-3,HK-II,and HIF-1 expressions as biomarkers for detecting primary tumors and lymph node metastasis with 18F-FDG-PET/CT.METHODS This retrospective study included 169 patients with colorectal cancer who underwent colectomy and preoperative 18F-FDG-PET/CT at Chungbuk National University Hospital between January 2009 and May 2012.Two tissue cores from the central and peripheral areas of the tumors were obtained and were examined by a dedicated pathologist,and the expressions of GLUT-1,GLUT-3,HK-II,and HIF-1 were determined using immunohisto-chemical staining.We analyzed the correlations among their expressions,various clinicopathological factors,and the maximum standardized uptake value(SUVmax)of PET/CT.RESULTS GLUT-1 was found at the center or periphery of the tumors in 109(64.5%)of the 169 patients.GLUT-1 positivity was significantly correlated with the SUVmax of the primary tumor and lymph nodes,regardless of the biopsy site(tumor center,P<0.001 and P=0.012;tumor periphery,P=0.030 and P=0.010,respectively).GLUT-1 positivity and negativity were associated with higher and lower sensitivities of PET/CT,respectively,for the detection of lymph node metastasis,regardless of the biopsy site.GLUT3,HK-II,and HIF-1 expressions were not significantly correlated with the SUVmax of the primary tumor and lymph nodes.CONCLUSION GLUT-1 expression was significantly correlated with the SUVmax of 18F-FDG-PET/CT for primary tumors and lymph nodes.Clinicians should consider GLUT-1 expression in preoperative endoscopic biopsy in interpreting PET/CT findings.展开更多
目的检测妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)孕妇血清程序性细胞死亡因子4(programmed cell death factor 4,PDCD4)和葡萄糖转运蛋白1(glucose transporter 1,GLUT1)的表达水平,分析二者与孕妇妊娠结局...目的检测妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)孕妇血清程序性细胞死亡因子4(programmed cell death factor 4,PDCD4)和葡萄糖转运蛋白1(glucose transporter 1,GLUT1)的表达水平,分析二者与孕妇妊娠结局的相关性。方法收集巴中市巴州区妇幼保健院产科2018年7月~2020年7月收治的ICP孕妇126例作为研究组,其中轻度ICP组46例,重度ICP组80例,选择同期该院120例健康产检孕妇作为对照组。采用实时荧光定量PCR(qRT-PCR)法测定ICP孕妇血清PDCD4和GLUT1水平,多因素Logistic回归分析影响ICP孕妇妊娠结局的因素,Pearson相关性分析ICP孕妇血清PDCD4和GLUT1水平的相关性。结果与对照组比较,研究组PDCD4(1.36±0.23 vs 1.02±0.21),GLUT1(1.40±0.22 vs 0.99±0.18)水平升高,差异具有统计学意义(t=15.935,12.090,均P=0.000)。重度ICP组PDCD4(1.41±0.25),GLUT1(1.45±0.22)水平显著高于轻度ICP组(1.27±0.20,1.31±0.21),差异具有统计学意义(t=3.246,3.496,均P<0.05)。研究组羊水胎粪污染(20.63%)、自发性早产(7.14%)、产后出血(8.73%)、宫内窘迫(11.90%)等不良妊娠结局的发生率均高于对照组(0.00%,0.83%,0.83%,1.67%),差异均具有统计学意义(χ^(2)=1.049~29.159,均P<0.05);妊娠结局良好组和妊娠结局不良组患者的发病程度(OR=1.109,95%CI=1.035~1.188)、PDCD4(OR=1.428,95%CI=1.013~2.012)以及GLUT1(OR=1.453,95%CI=1.066~1.980)水平差异具有统计学意义(均P<0.05);多因素Logistic回归分析显示,发病程度、PDCD4,GLUT1为ICP孕妇妊娠结局不良的影响因素(Waldχ^(2)==8.738,1.428,1.453;P=0.003,0.041,0.018);Pearson相关性分析显示,ICP孕妇血清PDCD4与GLUT1水平呈正相关(r=0.460,P<0.05)。结论PDCD4,GLUT1在ICP孕妇血清中表达均上调,二者呈正相关,是ICP孕妇妊娠结局不良的影响因素。展开更多
BACKGROUND Hepatic stellate cells(HSCs)are the key effector cells mediating the occurrence and development of liver fibrosis,while aerobic glycolysis is an important metabolic characteristic of HSC activation.Transfor...BACKGROUND Hepatic stellate cells(HSCs)are the key effector cells mediating the occurrence and development of liver fibrosis,while aerobic glycolysis is an important metabolic characteristic of HSC activation.Transforming growth factor-β1(TGF-β1)induces aerobic glycolysis and is a driving factor for metabolic reprogramming.The occurrence of glycolysis depends on a high glucose uptake level.Glucose transporter 1(GLUT1)is the most widely distributed glucose transporter in the body and mainly participates in the regulation of carbohydrate metabolism,thus affecting cell proliferation and growth.However,little is known about the relationship between TGF-β1 and GLUT1 in the process of liver fibrosis and the molecular mechanism underlying the promotion of aerobic glycolysis in HSCs.AIM To investigate the mechanisms of action of GLUT1,TGF-β1 and aerobic glycolysis in the process of HSC activation during liver fibrosis.METHODS Immunohistochemical staining and immunofluorescence assays were used to examine GLUT1 expression in fibrotic liver tissue.A Seahorse extracellular flux(XF)analyzer was used to examine changes in aerobic glycolytic flux,lactate production levels and glucose consumption levels in HSCs upon TGF-β1 stimulation.The mechanism by which TGF-β1 induces GLUT1 protein expression in HSCs was further explored by inhibiting/promoting the TGF-β1/mothersagainst-decapentaplegic-homolog 2/3(Smad2/3)signaling pathway and inhibiting the p38 and phosphoinositide 3-kinase(PI3K)/AKT signaling pathways.In addition,GLUT1 expression was silenced to observe changes in the growth and proliferation of HSCs.Finally,a GLUT1 inhibitor was used to verify the in vivo effects of GLUT1 on a mouse model of liver fibrosis.RESULTS GLUT1 protein expression was increased in both mouse and human fibrotic liver tissues.In addition,immunofluorescence staining revealed colocalization of GLUT1 and alpha-smooth muscle actin proteins,indicating that GLUT1 expression was related to the development of liver fibrosis.TGF-β1 caused an increase in aerobic glycolysis in HSCs and induced GLUT1 expression in HSCs by activating the Smad,p38 MAPK and P13K/AKT signaling pathways.The p38 MAPK and Smad pathways synergistically affected the induction of GLUT1 expression.GLUT1 inhibition eliminated the effect of TGF-β1 on HSC proliferation and migration.A GLUT1 inhibitor was administered in a mouse model of liver fibrosis,and GLUT1 inhibition reduced the degree of liver inflammation and liver fibrosis.CONCLUSION TGF-β1 induces GLUT1 expression in HSCs,a process related to liver fibrosis progression.In vitro experiments revealed that TGF-β1-induced GLUT1 expression might be one of the mechanisms mediating the metabolic reprogramming of HSCs.In addition,in vivo experiments also indicated that the GLUT1 protein promotes the occurrence and development of liver fibrosis.展开更多
Glucose transporter 1(GLUT1)overexpression in tumor cells is a potential target for drug therapy,but few studies have reported screening GLUT1 inhibitors from natural or synthetic compounds.With current analysis techn...Glucose transporter 1(GLUT1)overexpression in tumor cells is a potential target for drug therapy,but few studies have reported screening GLUT1 inhibitors from natural or synthetic compounds.With current analysis techniques,it is difficult to accurately monitor the GLUT1 inhibitory effect of drug molecules in real-time.We developed a cell membrane-based glucose sensor(CMGS)that integrated a hydrogel electrode with tumor cell membranes to monitor GLUT1 transmembrane transport and screen for GLUT1 inhibitors in traditional Chinese medicines(TCMs).CMGS is compatible with cell membranes of various origins,including different types of tumors and cell lines with GLUT1 expression knocked down by small interfering RNA or small molecules.Based on CMGS continuous monitoring technique,we investigated the glucose transport kinetics of cell membranes with varying levels of GLUT1 expression.We used CMGS to determine the GLUT1-inhibitory effects of drug monomers with similar structures from Scutellaria baicalensis and catechins families.Results were consistent with those of the cellular glucose uptake test and molecular-docking simulation.CMGS could accurately screen drug molecules in TCMs that inhibit GLUT1,providing a new strategy for studying transmembrane protein-receptor interactions.展开更多
BACKGROUND:The glucose transporter-1(Glut-1),a key ratelimiting factor in the transport and metabolism of glucose in cancer cells,is over-expressed in many human cancer cells and this overexpression is correlated with...BACKGROUND:The glucose transporter-1(Glut-1),a key ratelimiting factor in the transport and metabolism of glucose in cancer cells,is over-expressed in many human cancer cells and this overexpression is correlated with poor biological behavior. The increased levels of Glut-1 expression in hepatocellular carcinoma(HCC)cells functionally affect tumorigenicity.This study was undertaken to investigate effects of suppressing Glut-1 by an antisense oligodeoxynucleotide(AS-ODN)on the growth of human hepatocellular carcinoma(HepG-2)cells. METHODS:We used AS-ODN targeting against the Glut-1 gene in a HepG-2 cell line.There were four experimental groups: empty pcDNA3.1 vector(mock transfection),pcDNA3.1-anti-Glut(+),pcDNA3.1-Glut(+),and non-transfected HepG-2 cells. The Glut-1 mRNA expression was detected by RT-PCR and the Glut-1 protein expression by Western blotting after cell culture, and the glucose uptake was detected after glucose stimulation in each group. RESULTS:Compared with non-transfected HepG-2 or Glut-1 pcDNA3.1,a down-regulation of Glut-1 mRNA in HepG-2 cells transfected with anti-Glut-1 pcDNA3.1 was noted(P<0.05).Glut-1 protein in HepG-2 cells transfected with Glut-1 AS-ODN was decreased compared with non-transfected HepG-2,Glut-1 pcDNA3.1,or empty vectors. Glucose uptake by the HepG-2 cells transfected with AS-ODN was decreased at 1 hour after glucose stimulation.CONCLUSIONS:The application of Glut-1 AS-ODN can down-regulate the expression of Glut-1 at mRNA and protein,and inhibit glucose uptake partially in HepG-2 cells.The Glut-1 gene maybe a potential therapeutic target for HCC.展开更多
The interplay between mechanoresponses and a broad range of fundamental biological processes, such as cell cycle progression,growth and differentiation, has been extensively investigated. However, metabolic regulation...The interplay between mechanoresponses and a broad range of fundamental biological processes, such as cell cycle progression,growth and differentiation, has been extensively investigated. However, metabolic regulation in mechanobiology remains largely unexplored. Here, we identified glucose transporter 1(GLUT1)—the primary glucose transporter in various cells—as a novel mechanosensitive gene in orthodontic tooth movement(OTM). Using an in vivo rat OTM model, we demonstrated the specific induction of Glut1 proteins on the compressive side of a physically strained periodontal ligament. This transcriptional activation could be recapitulated in in vitro cultured human periodontal ligament cells(PDLCs), showing a time-and dose-dependent mechanoresponse. Importantly, application of GLUT1 specific inhibitor WZB117 greatly suppressed the efficiency of orthodontic tooth movement in a mouse OTM model, and this reduction was associated with a decline in osteoclastic activities. A mechanistic study suggested that GLUT1 inhibition affected the receptor activator for nuclear factor-κ B Ligand(RANKL)/osteoprotegerin(OPG)system by impairing compressive force-mediated RANKL upregulation. Consistently, pretreatment of PDLCs with WZB117 severely impeded the osteoclastic differentiation of co-cultured RAW264.7 cells. Further biochemical analysis indicated mutual regulation between GLUT1 and the MEK/ERK cascade to relay potential communication between glucose uptake and mechanical stress response. Together, these cross-species experiments revealed the transcriptional activation of GLUT1 as a novel and conserved linkage between metabolism and bone remodelling.展开更多
BACKGROUND Gestational diabetes mellitus(GDM)women require prenatal care to minimize short-and long-term complications.The mechanism by which exercise during pregnancy affects organ development and whether glucose tra...BACKGROUND Gestational diabetes mellitus(GDM)women require prenatal care to minimize short-and long-term complications.The mechanism by which exercise during pregnancy affects organ development and whether glucose transporter(GLUT)1 plays a role in GDM offspring organ development remains unknown.AIM To determine the effect of exercise during pregnancy on the cardiac,hepatic and renal development of GDM mother’s offspring.METHODS Placenta samples were collected from humans and mice.GDM mouse models were created using streptozotocin along with a GDM with exercise group.The hearts,livers and kidneys of 3-and 8-week-old offspring were collected for body composition analysis and staining.The effects of high glucose levels and hypoxia were investigated using HTR8/SVneo.Transwell and wound-healing assays were performed to assess cell migration.Immunofluorescence accompanied with TUNEL and Ki67 staining was used to explore apoptosis and proliferation.RESULTS Exercise during pregnancy downregulated the GLUT1 and hypoxia inducible factor-1αexpression in placenta from individuals with GDM.Cobalt chloride induced hypoxia and high glucose levels also significantly decreased migration and apoptosis of HTR8/SVneo cells.In addition,exercise reduced inflammatory cell infiltration in the liver and decreased the tubular vacuolar area in the kidneys of offspring.CONCLUSION GDM affects the growth and development of organs in offspring.Exercise during pregnancy can reverse adverse effects of GDM on the development of the heart,liver,and kidney in offspring.展开更多
BACKGROUND： We constructed a homologous recombination bacterial method based on the pAdEasy system, a widely used system, for generating recombinant adenoviral vectors that express glucose transporter- 1 （GLUT 1） i...BACKGROUND： We constructed a homologous recombination bacterial method based on the pAdEasy system, a widely used system, for generating recombinant adenoviral vectors that express glucose transporter- 1 （GLUT 1） in rats, OBJECTIVE： This study was designed to investigate the feasibility of generating recombinant replication-defective adenoviral vectors that express GLUT1 in rats by in vitro ligation based on the Adeno-X^TM system. DESIGN： An in vitro cell-based experiment. SETTING： This study was performed at the Linbaixin Medical Research Center of the Second Hospital Affiliated to Sun Yat-sen University and Central Laboratory for Prevention and Treatment of Tumor, Sun Yat-sen University between January and August 2004. MATERIALS： Male, adult, Sprague Dawley rats were used to extract total RNA from brain tissue. E. coli DH5 a and human embryonic kidney 293 cells （HEK293 cells） used in the present study were cryo-preserved by the Second Hospital Affiliated to Sun Yat-sen University. Rabbit anti-rat GLUT1 polyclonal antibody （Chemicon, U.S.A.） and primers （Shanghai Boya Bioengineering Co., Ltd） were also used. METHODS： E1/E3-deleted replication-defective adenoviral vectors were used. Using in vitro ligation, the target gene was first sub-cloned into a shuttle vector plasmid to obtain the fragment containing target gene expression cassettes by enzyme digestion. Subsequently, the fragment was co-transformed with linearized adenoviral backbone vector into the E. coli strain. The recombinant adenoviral plasmid was transfected into HEK293 cells to assembly recombinant adenoviral vectors with replication capabilities. The procedure was repeated several times for recombinant adenoviral vectors amplification. MAIN OUTCOME MEASURES： Efficiency of recombinant adenoviral vectors to express the target gene was measured by gene and protein expression through polymerase chain reaction and Western Blot assays, respectively. RESULTS： Results demonstrated that recombinant adenoviral vectors successfully expressed GLUT1 protein, with a relative molecular mass of 55000 in HEK293 cells. These results suggest that recombinant adenoviral vectors obtained by homologous bacterial recombination feature high efficiency, rapidness, and simplicity. CONCLUSION： We successfully amplified the rat GLUT1 gene and constructed replication-defective adenoviral vectors expressing GLUT1. The replication-defective adenoviral vectors proved to successfully express the target gene in HEK293 cells.展开更多
文摘BACKGROUND There are limited data on the use of glucose transport protein 1(GLUT-1)expre-ssion as a biomarker for predicting lymph node metastasis in patients with colorectal cancer.GLUT-1 and GLUT-3,hexokinase(HK)-II,and hypoxia-induced factor(HIF)-1 expressions may be useful biomarkers for detecting primary tumors and lymph node metastasis when combined with fluorodeoxyglucose(FDG)uptake on positron emission tomography/computed tomography(PET/CT).AIM To evaluate GLUT-1,GLUT-3,HK-II,and HIF-1 expressions as biomarkers for detecting primary tumors and lymph node metastasis with 18F-FDG-PET/CT.METHODS This retrospective study included 169 patients with colorectal cancer who underwent colectomy and preoperative 18F-FDG-PET/CT at Chungbuk National University Hospital between January 2009 and May 2012.Two tissue cores from the central and peripheral areas of the tumors were obtained and were examined by a dedicated pathologist,and the expressions of GLUT-1,GLUT-3,HK-II,and HIF-1 were determined using immunohisto-chemical staining.We analyzed the correlations among their expressions,various clinicopathological factors,and the maximum standardized uptake value(SUVmax)of PET/CT.RESULTS GLUT-1 was found at the center or periphery of the tumors in 109(64.5%)of the 169 patients.GLUT-1 positivity was significantly correlated with the SUVmax of the primary tumor and lymph nodes,regardless of the biopsy site(tumor center,P<0.001 and P=0.012;tumor periphery,P=0.030 and P=0.010,respectively).GLUT-1 positivity and negativity were associated with higher and lower sensitivities of PET/CT,respectively,for the detection of lymph node metastasis,regardless of the biopsy site.GLUT3,HK-II,and HIF-1 expressions were not significantly correlated with the SUVmax of the primary tumor and lymph nodes.CONCLUSION GLUT-1 expression was significantly correlated with the SUVmax of 18F-FDG-PET/CT for primary tumors and lymph nodes.Clinicians should consider GLUT-1 expression in preoperative endoscopic biopsy in interpreting PET/CT findings.
文摘目的检测妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)孕妇血清程序性细胞死亡因子4(programmed cell death factor 4,PDCD4)和葡萄糖转运蛋白1(glucose transporter 1,GLUT1)的表达水平,分析二者与孕妇妊娠结局的相关性。方法收集巴中市巴州区妇幼保健院产科2018年7月~2020年7月收治的ICP孕妇126例作为研究组,其中轻度ICP组46例,重度ICP组80例,选择同期该院120例健康产检孕妇作为对照组。采用实时荧光定量PCR(qRT-PCR)法测定ICP孕妇血清PDCD4和GLUT1水平,多因素Logistic回归分析影响ICP孕妇妊娠结局的因素,Pearson相关性分析ICP孕妇血清PDCD4和GLUT1水平的相关性。结果与对照组比较,研究组PDCD4(1.36±0.23 vs 1.02±0.21),GLUT1(1.40±0.22 vs 0.99±0.18)水平升高,差异具有统计学意义(t=15.935,12.090,均P=0.000)。重度ICP组PDCD4(1.41±0.25),GLUT1(1.45±0.22)水平显著高于轻度ICP组(1.27±0.20,1.31±0.21),差异具有统计学意义(t=3.246,3.496,均P<0.05)。研究组羊水胎粪污染(20.63%)、自发性早产(7.14%)、产后出血(8.73%)、宫内窘迫(11.90%)等不良妊娠结局的发生率均高于对照组(0.00%,0.83%,0.83%,1.67%),差异均具有统计学意义(χ^(2)=1.049~29.159,均P<0.05);妊娠结局良好组和妊娠结局不良组患者的发病程度(OR=1.109,95%CI=1.035~1.188)、PDCD4(OR=1.428,95%CI=1.013~2.012)以及GLUT1(OR=1.453,95%CI=1.066~1.980)水平差异具有统计学意义(均P<0.05);多因素Logistic回归分析显示,发病程度、PDCD4,GLUT1为ICP孕妇妊娠结局不良的影响因素(Waldχ^(2)==8.738,1.428,1.453;P=0.003,0.041,0.018);Pearson相关性分析显示,ICP孕妇血清PDCD4与GLUT1水平呈正相关(r=0.460,P<0.05)。结论PDCD4,GLUT1在ICP孕妇血清中表达均上调,二者呈正相关,是ICP孕妇妊娠结局不良的影响因素。
基金by National Natural Science Foundation of China,No.82060116,No.81860115 and No.81960118Guizhou Science and Technology Support Project Fund,No.[2021]058.
文摘BACKGROUND Hepatic stellate cells(HSCs)are the key effector cells mediating the occurrence and development of liver fibrosis,while aerobic glycolysis is an important metabolic characteristic of HSC activation.Transforming growth factor-β1(TGF-β1)induces aerobic glycolysis and is a driving factor for metabolic reprogramming.The occurrence of glycolysis depends on a high glucose uptake level.Glucose transporter 1(GLUT1)is the most widely distributed glucose transporter in the body and mainly participates in the regulation of carbohydrate metabolism,thus affecting cell proliferation and growth.However,little is known about the relationship between TGF-β1 and GLUT1 in the process of liver fibrosis and the molecular mechanism underlying the promotion of aerobic glycolysis in HSCs.AIM To investigate the mechanisms of action of GLUT1,TGF-β1 and aerobic glycolysis in the process of HSC activation during liver fibrosis.METHODS Immunohistochemical staining and immunofluorescence assays were used to examine GLUT1 expression in fibrotic liver tissue.A Seahorse extracellular flux(XF)analyzer was used to examine changes in aerobic glycolytic flux,lactate production levels and glucose consumption levels in HSCs upon TGF-β1 stimulation.The mechanism by which TGF-β1 induces GLUT1 protein expression in HSCs was further explored by inhibiting/promoting the TGF-β1/mothersagainst-decapentaplegic-homolog 2/3(Smad2/3)signaling pathway and inhibiting the p38 and phosphoinositide 3-kinase(PI3K)/AKT signaling pathways.In addition,GLUT1 expression was silenced to observe changes in the growth and proliferation of HSCs.Finally,a GLUT1 inhibitor was used to verify the in vivo effects of GLUT1 on a mouse model of liver fibrosis.RESULTS GLUT1 protein expression was increased in both mouse and human fibrotic liver tissues.In addition,immunofluorescence staining revealed colocalization of GLUT1 and alpha-smooth muscle actin proteins,indicating that GLUT1 expression was related to the development of liver fibrosis.TGF-β1 caused an increase in aerobic glycolysis in HSCs and induced GLUT1 expression in HSCs by activating the Smad,p38 MAPK and P13K/AKT signaling pathways.The p38 MAPK and Smad pathways synergistically affected the induction of GLUT1 expression.GLUT1 inhibition eliminated the effect of TGF-β1 on HSC proliferation and migration.A GLUT1 inhibitor was administered in a mouse model of liver fibrosis,and GLUT1 inhibition reduced the degree of liver inflammation and liver fibrosis.CONCLUSION TGF-β1 induces GLUT1 expression in HSCs,a process related to liver fibrosis progression.In vitro experiments revealed that TGF-β1-induced GLUT1 expression might be one of the mechanisms mediating the metabolic reprogramming of HSCs.In addition,in vivo experiments also indicated that the GLUT1 protein promotes the occurrence and development of liver fibrosis.
基金supported by the National Natural Science Foundation of China,China(Grant Nos.:61801160 and 81730108).
文摘Glucose transporter 1(GLUT1)overexpression in tumor cells is a potential target for drug therapy,but few studies have reported screening GLUT1 inhibitors from natural or synthetic compounds.With current analysis techniques,it is difficult to accurately monitor the GLUT1 inhibitory effect of drug molecules in real-time.We developed a cell membrane-based glucose sensor(CMGS)that integrated a hydrogel electrode with tumor cell membranes to monitor GLUT1 transmembrane transport and screen for GLUT1 inhibitors in traditional Chinese medicines(TCMs).CMGS is compatible with cell membranes of various origins,including different types of tumors and cell lines with GLUT1 expression knocked down by small interfering RNA or small molecules.Based on CMGS continuous monitoring technique,we investigated the glucose transport kinetics of cell membranes with varying levels of GLUT1 expression.We used CMGS to determine the GLUT1-inhibitory effects of drug monomers with similar structures from Scutellaria baicalensis and catechins families.Results were consistent with those of the cellular glucose uptake test and molecular-docking simulation.CMGS could accurately screen drug molecules in TCMs that inhibit GLUT1,providing a new strategy for studying transmembrane protein-receptor interactions.
文摘BACKGROUND:The glucose transporter-1(Glut-1),a key ratelimiting factor in the transport and metabolism of glucose in cancer cells,is over-expressed in many human cancer cells and this overexpression is correlated with poor biological behavior. The increased levels of Glut-1 expression in hepatocellular carcinoma(HCC)cells functionally affect tumorigenicity.This study was undertaken to investigate effects of suppressing Glut-1 by an antisense oligodeoxynucleotide(AS-ODN)on the growth of human hepatocellular carcinoma(HepG-2)cells. METHODS:We used AS-ODN targeting against the Glut-1 gene in a HepG-2 cell line.There were four experimental groups: empty pcDNA3.1 vector(mock transfection),pcDNA3.1-anti-Glut(+),pcDNA3.1-Glut(+),and non-transfected HepG-2 cells. The Glut-1 mRNA expression was detected by RT-PCR and the Glut-1 protein expression by Western blotting after cell culture, and the glucose uptake was detected after glucose stimulation in each group. RESULTS:Compared with non-transfected HepG-2 or Glut-1 pcDNA3.1,a down-regulation of Glut-1 mRNA in HepG-2 cells transfected with anti-Glut-1 pcDNA3.1 was noted(P<0.05).Glut-1 protein in HepG-2 cells transfected with Glut-1 AS-ODN was decreased compared with non-transfected HepG-2,Glut-1 pcDNA3.1,or empty vectors. Glucose uptake by the HepG-2 cells transfected with AS-ODN was decreased at 1 hour after glucose stimulation.CONCLUSIONS:The application of Glut-1 AS-ODN can down-regulate the expression of Glut-1 at mRNA and protein,and inhibit glucose uptake partially in HepG-2 cells.The Glut-1 gene maybe a potential therapeutic target for HCC.
基金supported by the National Natural Science Foundation of China (# 81502345 to Qian Li and #81470717 to Yanheng Zhou)the International Science & Technology Cooperation Program of China (#2015DFB30040 to Yanheng Zhou)
文摘The interplay between mechanoresponses and a broad range of fundamental biological processes, such as cell cycle progression,growth and differentiation, has been extensively investigated. However, metabolic regulation in mechanobiology remains largely unexplored. Here, we identified glucose transporter 1(GLUT1)—the primary glucose transporter in various cells—as a novel mechanosensitive gene in orthodontic tooth movement(OTM). Using an in vivo rat OTM model, we demonstrated the specific induction of Glut1 proteins on the compressive side of a physically strained periodontal ligament. This transcriptional activation could be recapitulated in in vitro cultured human periodontal ligament cells(PDLCs), showing a time-and dose-dependent mechanoresponse. Importantly, application of GLUT1 specific inhibitor WZB117 greatly suppressed the efficiency of orthodontic tooth movement in a mouse OTM model, and this reduction was associated with a decline in osteoclastic activities. A mechanistic study suggested that GLUT1 inhibition affected the receptor activator for nuclear factor-κ B Ligand(RANKL)/osteoprotegerin(OPG)system by impairing compressive force-mediated RANKL upregulation. Consistently, pretreatment of PDLCs with WZB117 severely impeded the osteoclastic differentiation of co-cultured RAW264.7 cells. Further biochemical analysis indicated mutual regulation between GLUT1 and the MEK/ERK cascade to relay potential communication between glucose uptake and mechanical stress response. Together, these cross-species experiments revealed the transcriptional activation of GLUT1 as a novel and conserved linkage between metabolism and bone remodelling.
基金Supported by Key R and D Program of Zhejiang Province,No.2022C03058Medical and Health Technology Program of Zhejiang Province,No.WKJ-ZJ-2324and 4+X Clinical Research Project of Women's Hospital,School of Medicine,Zhejiang University,No.ZDFY2022-4XB101.
文摘BACKGROUND Gestational diabetes mellitus(GDM)women require prenatal care to minimize short-and long-term complications.The mechanism by which exercise during pregnancy affects organ development and whether glucose transporter(GLUT)1 plays a role in GDM offspring organ development remains unknown.AIM To determine the effect of exercise during pregnancy on the cardiac,hepatic and renal development of GDM mother’s offspring.METHODS Placenta samples were collected from humans and mice.GDM mouse models were created using streptozotocin along with a GDM with exercise group.The hearts,livers and kidneys of 3-and 8-week-old offspring were collected for body composition analysis and staining.The effects of high glucose levels and hypoxia were investigated using HTR8/SVneo.Transwell and wound-healing assays were performed to assess cell migration.Immunofluorescence accompanied with TUNEL and Ki67 staining was used to explore apoptosis and proliferation.RESULTS Exercise during pregnancy downregulated the GLUT1 and hypoxia inducible factor-1αexpression in placenta from individuals with GDM.Cobalt chloride induced hypoxia and high glucose levels also significantly decreased migration and apoptosis of HTR8/SVneo cells.In addition,exercise reduced inflammatory cell infiltration in the liver and decreased the tubular vacuolar area in the kidneys of offspring.CONCLUSION GDM affects the growth and development of organs in offspring.Exercise during pregnancy can reverse adverse effects of GDM on the development of the heart,liver,and kidney in offspring.
基金the National Natural Science Foundation of China, No. 39900048the Natural Science Foundation of Guangdong Province, No.010721
文摘BACKGROUND： We constructed a homologous recombination bacterial method based on the pAdEasy system, a widely used system, for generating recombinant adenoviral vectors that express glucose transporter- 1 （GLUT 1） in rats, OBJECTIVE： This study was designed to investigate the feasibility of generating recombinant replication-defective adenoviral vectors that express GLUT1 in rats by in vitro ligation based on the Adeno-X^TM system. DESIGN： An in vitro cell-based experiment. SETTING： This study was performed at the Linbaixin Medical Research Center of the Second Hospital Affiliated to Sun Yat-sen University and Central Laboratory for Prevention and Treatment of Tumor, Sun Yat-sen University between January and August 2004. MATERIALS： Male, adult, Sprague Dawley rats were used to extract total RNA from brain tissue. E. coli DH5 a and human embryonic kidney 293 cells （HEK293 cells） used in the present study were cryo-preserved by the Second Hospital Affiliated to Sun Yat-sen University. Rabbit anti-rat GLUT1 polyclonal antibody （Chemicon, U.S.A.） and primers （Shanghai Boya Bioengineering Co., Ltd） were also used. METHODS： E1/E3-deleted replication-defective adenoviral vectors were used. Using in vitro ligation, the target gene was first sub-cloned into a shuttle vector plasmid to obtain the fragment containing target gene expression cassettes by enzyme digestion. Subsequently, the fragment was co-transformed with linearized adenoviral backbone vector into the E. coli strain. The recombinant adenoviral plasmid was transfected into HEK293 cells to assembly recombinant adenoviral vectors with replication capabilities. The procedure was repeated several times for recombinant adenoviral vectors amplification. MAIN OUTCOME MEASURES： Efficiency of recombinant adenoviral vectors to express the target gene was measured by gene and protein expression through polymerase chain reaction and Western Blot assays, respectively. RESULTS： Results demonstrated that recombinant adenoviral vectors successfully expressed GLUT1 protein, with a relative molecular mass of 55000 in HEK293 cells. These results suggest that recombinant adenoviral vectors obtained by homologous bacterial recombination feature high efficiency, rapidness, and simplicity. CONCLUSION： We successfully amplified the rat GLUT1 gene and constructed replication-defective adenoviral vectors expressing GLUT1. The replication-defective adenoviral vectors proved to successfully express the target gene in HEK293 cells.
