BACKGROUND Synaptotagmins(SYTs)are a family of 17 membrane transporters that function as calcium ion sensors during the release of Ca2+-dependent neurotransmitters and hormones.However,few studies have reported whethe...BACKGROUND Synaptotagmins(SYTs)are a family of 17 membrane transporters that function as calcium ion sensors during the release of Ca2+-dependent neurotransmitters and hormones.However,few studies have reported whether members of the SYT family play a role in glucose uptake in diabetic retinopathy(DR)through Ca2+/glucose transporter-1(GLUT1)and the possible regulatory mechanism of SYTs.AIM To elucidate the role of the SYT family in the regulation of glucose transport in retinal pigment epithelial cells and explore its potential as a therapeutic target for the clinical management of DR.METHODS DR was induced by streptozotocin in C57BL/6J mice and by high glucose medium in human retinal pigment epithelial cells(ARPE-19).Bioinformatics analysis,reverse transcriptase-polymerase chain reaction,Western blot,flow cytometry,ELISA,HE staining,and TUNEL staining were used for analysis.RESULTS Six differentially expressed proteins(SYT2,SYT3,SYT4,SYT7,SYT11,and SYT13)were found between the DR and control groups,and SYT4 was highly expressed.Hyperglycemia induces SYT4 overexpression,manipulates Ca2+influx to induce GLUT1 fusion with the plasma membrane,promotes abnormal expression of the glucose transporter GLUT1 and excessive glucose uptake,induces ARPE-19 cell apoptosis,and promotes DR progression.Parkin deficiency inhibits the proteasomal degradation of SYT4 in DR,resulting in SYT4 accumulation and enhanced GLUT1 fusion with the plasma membrane,and these effects were blocked by oe-Parkin treatment.Moreover,dysregulation of the myelin transcription factor 1(Myt1)-induced transcription of SYT4 in DR further activated the SYT4-mediated stimulus-secretion coupling process,and this process was inhibited in the oe-MYT1-treated group.CONCLUSION Our study reveals the key role of SYT4 in regulating glucose transport in retinal pigment epithelial cells during the pathogenesis of DR and the underlying mechanism and suggests potential therapeutic targets for clinical DR.展开更多
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
Managing diabetes during pregnancy is challenging,given the significant risk it poses for both maternal and foetal health outcomes.While traditional methods involve capillary self-monitoring of blood glucose level mon...Managing diabetes during pregnancy is challenging,given the significant risk it poses for both maternal and foetal health outcomes.While traditional methods involve capillary self-monitoring of blood glucose level monitoring and periodic HbA1c tests,the advent of continuous glucose monitoring(CGM)systems has revolutionized the approach.These devices offer a safe and reliable means of tracking glucose levels in real-time,benefiting both women with diabetes during pregnancy and the healthcare providers.Moreover,CGM systems have shown a low rate of side effects and high feasibility when used in pregnancies complicated by diabetes,especially when paired with continuous subcutaneous insulin infusion pump as hybrid closed loop device.Such a combined approach has been demonstrated to improve overall blood sugar control,lessen the occurrence of preeclampsia and neonatal hypoglycaemia,and minimize the duration of neonatal intensive care unit stays.This paper aims to offer a comprehensive evaluation of CGM metrics specifically tailored for pregnancies impacted by type 1 diabetes mellitus.展开更多
AIM:To evaluate the effects of LIN28A(human)on high glucose-induced retinal pigmented epithelium(RPE)cell injury and its possible mechanism.METHODS:Diabetic retinopathy model was generated following 48h of exposure to...AIM:To evaluate the effects of LIN28A(human)on high glucose-induced retinal pigmented epithelium(RPE)cell injury and its possible mechanism.METHODS:Diabetic retinopathy model was generated following 48h of exposure to 30 mmol/L high glucose(HG)in ARPE-19 cells.Quantitative real-time polymerase chain reaction(qRT-PCR)and Western blot tested the expression of the corresponding genes and proteins.Cell viability as well as apoptosis was determined through cell counting kit-8(CCK-8)and flow cytometry assays.Immunofluorescence assay was adopted to evaluate autophagy activity.Caspase 3 activity,oxidative stress markers,and cytokines were appraised adopting their commercial kits,respectively.Finally,ARPE-19 cells were preincubated with EX527,a Sirtuin 1(SIRT1)inhibitor,prior to HG stimulation to validate the regulatory mechanism.RESULTS:LIN28A was downregulated in HG-challenged ARPE-19 cells.LIN28A overexpression greatly inhibited HGinduced ARPE-19 cell viability loss,apoptosis,oxidative damage as well as inflammatory response.Meanwhile,the repressed autophagy and SIRT1 in ARPE-19 cells challenged with HG were elevated after LIN28A overexpression.In addition,treatment of EX527 greatly inhibited the activated autophagy following LIN28A overexpression and partly abolished the protective role of LIN28A against HG-elicited apoptosis,oxidative damage as well as inflammation in ARPE-19 cells.CONCLUSION:LIN28A exerts a protective role against HG-elicited RPE oxidative damage,inflammation,as well as apoptosis via regulating SIRT1/autophagy.展开更多
The global commitment to pivoting to sustainable energy and products calls for technology development to utilize solar energy for hydrogen(H_(2))and value-added chemicals production by biomass photoreforming.Herein,a ...The global commitment to pivoting to sustainable energy and products calls for technology development to utilize solar energy for hydrogen(H_(2))and value-added chemicals production by biomass photoreforming.Herein,a novel dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction has been the production of lactic acid with high-yield and H_(2)with high-efficiency by selective glucose photoreforming.The optimized Zn_(0.3)Cd_(0.7)S exhibits outstanding H_(2)generation(13.64 mmol h^(-1)g^(-1)),glucose conversion(96.40%),and lactic acid yield(76.80%),over 272.80 and 19.21 times higher than that of bare ZnS(0.05 mmol h^(-1)g^(-1))and CdS(0.71 mmol h^(-1)g^(-1))in H_(2)generation,respectively.The marigold-like morphology provides abundant active sites and sufficient substrates accessibility for the photocatalyst,while the specific role of the homojunction formed by hexagonal wurtzite(WZ)and cubic zinc blende(ZB)in photoreforming biomass has been demonstrated by density functional theory(DFT)calculations.Glucose is converted to lactic acid on the WZ surface of Zn_(0.3)Cd_(0.7)S via the photoactive species·O_(2)^(-),while the H_(2)is evolved from protons(H^(+))in H_(2)O on the ZB surface of Zn_(0.3)Cd_(0.7)S.This work paves a promising road for the production of sustainable energy and products by integrating photocatalysis and biorefine.展开更多
BACKGROUND The small intestine is known to play a crucial role in the development and remission of diabetes mellitus(DM).However,the exact mechanism by which mid-small intestinal bypass improves glucose metabolism in ...BACKGROUND The small intestine is known to play a crucial role in the development and remission of diabetes mellitus(DM).However,the exact mechanism by which mid-small intestinal bypass improves glucose metabolism in diabetic rats is not fully understood.AIM To elucidate the mechanisms by which mid-small intestinal bypass improves glucose metabolism.METHODS Streptozotocin(STZ)was used to induce DM in Sprague-Dawley(SD)rats at a dose of 60 mg/kg.The rats were then randomly divided into two groups:The mid-small intestine bypass(MSIB)group and the sham group(underwent switch laparotomy).Following a 6-wk recovery period post-surgery,the rats underwent various assessments,including metabolic parameter testing,analysis of liver glycogen levels,measurement of key gluconeogenic enzyme activity,characterization of the gut microbiota composition,evaluation of hormone levels,determination of bile acid concentrations,and assessment of the expression of the intestinal receptors Takeda G protein-coupled receptor 5 and farnesoid X receptor.RESULTS The MSIB group of rats demonstrated improved glucose metabolism and lipid metabolism,along with increased hepatic glycogen content.Furthermore,there was a decrease in the expression of the key gluconeogenic enzymes phosphoenolpyruvate carboxykinase 1 and glucose-6-phosphatase.Importantly,the MSIB group exhibited a substantial increase in the abundances of intestinal Lactobacillus,Clostridium symbiosum,Ruminococcus gnavus,and Bilophila.Moreover,higher levels of secondary bile acids,such as intestinal lithocholic acid,were observed in this group.Remarkably,the changes in the gut microbiota showed a significant correlation with the expression of key gluconeogenic enzymes and glucagon-like peptide 1(GLP-1)at 6 wk postoperatively,highlighting their potential role in glucose regulation.These findings highlight the beneficial effects of mid-small intestine bypass on glucose metabolism and the associated modulation of the gut microbiota.CONCLUSION The findings of this study demonstrate that the introduction of postoperative intestinal Clostridium symbiosum in the mid-small intestine contributes to the enhancement of glucose metabolism in nonobese diabetic rats.This improvement is attributed to the increased inhibition of hepatic gluconeogenesis mediated by GLP-1,resulting in a favorable modulation of glucose homeostasis.展开更多
Objective:To explore the regulatory mechanism of transient receptor potential melastatin-7(TRPM7)in high glucose-induced renal tubular epithelial cell injury.Methods:The expression of TRPM7 in the serum of diabetic ne...Objective:To explore the regulatory mechanism of transient receptor potential melastatin-7(TRPM7)in high glucose-induced renal tubular epithelial cell injury.Methods:The expression of TRPM7 in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells was detected by RT-qPCR.Then,the TRPM7 interference vector was constructed,and the downstream high mobility group box 1(HMGB1)/Toll-like receptor 4(TLR4)signaling pathway proteins were detected.Next,in addition to interference with TRPM7 expression,overexpression of HMGB1 in high glucose-induced HK-2 cells was performed.Cell activity,apoptosis,oxidative stress levels,and inflammation levels were determined by CCK8,TUNEL,Western blotting,immunofluorescence and related kits.Results:TRPM7 expression was upregulated in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells.Interference with TRPM7 reduced cell damage,epithelial-mesenchymal transition,oxidative stress,and inflammatory response in high glucose-induced HK-2 cells via inhibiting the HMGB1/TLR4 signaling pathway.However,the effects induced by TRPM7 silencing were abrogated by HMGB1 overexpression.Conclusions:Decreased TRPM7 alleviates high glucose-induced renal tubular epithelial cell injury by inhibiting the HMGB1/TLR4 signaling pathway.Further animal experiments and clinical trials are warranted to verify its effect.展开更多
BACKGROUND Currently,the lack of comparative studies between weekly and daily formulations of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for glucose excursion is worth investigation.AIM To investigate the effe...BACKGROUND Currently,the lack of comparative studies between weekly and daily formulations of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for glucose excursion is worth investigation.AIM To investigate the effects of weekly and daily formulations of GLP-1RA on glucose excursion and inflammation in overweight and obese patients with type 2 diabetes.METHODS Seventy patients with type 2 diabetes mellitus who were treated at our hospital between January 2019 and January 2022 were enrolled in this retrospective analysis.All patients were treated with metformin.We evaluated changes in blood glucose levels and a series of important indicators in patients before and after treatment with either a weekly or daily preparation of GLP-1RA(group A;n=33 and group B;n=37).RESULTS The degree of decrease in the levels of fasting blood glucose,mean blood glucose,mean amplitude of glycemic excursions,total cholesterol,triglycerides,tumor necrosis factor-α,interleukin-6,and high-sensitivity C-reactive protein after treatment in group A was higher than that in group B(P<0.05),whereas the 2-h postprandial blood glucose levels decreased more so in group B than in group A(P<0.001).However,there were no statistically significant differences in the levels of glycated hemoglobin,standard deviation of blood glucose,coefficient of variation,absolute mean of daily differences,percentage of time with 3.9 mmol/L<glucose<10 mmol/L,and high-and low-density lipoproteins between the two groups(P>0.05).The incidence of adverse reactions was significantly lower in group A than in group B(P<0.05).CONCLUSION The effect of the weekly preparation of GLP-1RA in controlling blood glucose levels in the patients,suppressing inflammation,and reducing adverse reactions was significantly higher than that of the daily preparations,which is worthy of clinical promotion.展开更多
Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC...Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC),high-fat diet(HFD),HFD with low-dose CGA(20 mg/kg,HFD-LC),and HFD with high-dose CGA(90 mg/kg,HFD-HC).The oral glucose tolerance test was performed,and fast serum insulin(FSI)was detected using an enzyme-linked immunosorbent assay.The m RNA expression levels of glucose transporters(Sglt-1 and Glut-2)and proglucagon(Plg)in different intestinal segments(the duodenum,jejunum,ileum,and colon)were analyzed using quantitative real-time polymerase chain reaction.SGLT-1 protein and the morphology of epithelial cells in the duodenum and jejunum was localized by using immunofluorescence.Results At both doses,CGA ameliorated the HFD-induced body weight gain,maintained FSI,and increased postprandial 30-min glucagon-like peptide 1 secretion.High-dose CGA inhibited the HFD-induced elevation in Sglt-1 expression.Both CGA doses normalized the HFD-induced downregulation of Glut-2 and elevated the expression of Plg in all four intestinal segments.Conclusion An HFD can cause a glucose metabolism disorder in the rat intestine and affect body glucose homeostasis.CGA can modify intestinal glucose metabolism by regulating the expression of intestinal glucose transporters and Plg,thereby controlling the levels of blood glucose and insulin to maintain glucose homeostasis.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
OBJECTIVE To investigate the protective effect of icariin(ICA) on learning and memory function in APP/PS1/Tau triple transgenic Alzheimer disease mice(3×Tg-AD mice),and then to explore whether its mechanism is re...OBJECTIVE To investigate the protective effect of icariin(ICA) on learning and memory function in APP/PS1/Tau triple transgenic Alzheimer disease mice(3×Tg-AD mice),and then to explore whether its mechanism is related to the improvement of brain glucose metabolism disorder.METHODS Three-month-old male 3 ×Tg-AD mice were randomly divided into three groups(n=10):3×Tg group,3×Tg+ICA low-dose group(30 mg·kg-1) and 3×Tg + ICA high-dose group(60 mg·kg-1).Age-matched male wild type(WT) mice were randomly divided into two groups(n=10):WT control group and WT+ICA60 mg·kg-1 group.ICA in vehicle(0.5% Tween-80 in distilled water) was given orally once a day for five months in the 3×Tg+ICA groups.3×Tg and WT control group were given an equal volume vehicle.Morris water maze was used to detect the learning and memory function of mice.Brain glucose metabolism in 3×Tg mice was observed by 18 F-FDG microPET imaging technique.Nissl staining and HE staining were used to evaluate the survival neurons in hippocampus of mice.Glucose oxidase assay was used to detect glucose contents in cortex of mice.The protein expression of APP,Aβ1-40,Aβ1-42 and glucose transporter 1(GLUT1),and the phosphorylation level of tau protein at multiple sites in hippocampus were detected by Western blotting.RESULTS Behavioral examination revealed a profound decrease learning and memory function,accompanied by a decrease in number of neuronal cells in 3×Tg-AD mice.Moreover,the cerebral18 F-FDG uptake rate per gram tissue was reduced and the glucose contents in the cortex were increased in 3×Tg-AD mice.In addition,Western blotting analysis showed that the expression of APP,Aβ1-40,Aβ1-42 proteins and the levels of tau protein phosphorylation at Ser199/202 and PHF-1(Ser396/404) sites were increased significantly,followed by a decrease of GLUT1 expression in hippocampus of 3×Tg-AD mice.All of these changes in behavioral functions,neuronal loss and related protein expression were reversed when mice were treated with ICA.CONCLUSION ICA can improve the learning and memory ability of AD model mice,the mechanism may be related to the improvement of cerebral glucose metabolism dysfunction by increasing the expression of GLUT1.展开更多
The role of serum and glucocorticoid-induced kinase 1 (SGK1) pathway in the connective tissue growth factor (CTGF) expression was investigated in cultured human mesangial cells (HMCs) under high glucose. By usin...The role of serum and glucocorticoid-induced kinase 1 (SGK1) pathway in the connective tissue growth factor (CTGF) expression was investigated in cultured human mesangial cells (HMCs) under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 (SD) could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP (FP) under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 (KN) could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.展开更多
Summary: In order to explore the effect of high glucose concentration and high glucose concentration with hypoxia on the production of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor ...Summary: In order to explore the effect of high glucose concentration and high glucose concentration with hypoxia on the production of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF), human RPE cells were cultured in 5,56 mmol/L glucose (control group), 5.56 mmol/L glucose with 150 !a mol/L COCl2 (hypoxic group), 25 mmol/L glucose (high glucose group) and 25 mmol/L glucose with 150 μmol/L COCl2 (combination group). RT-PCR was used to detect the expression of HIF-1α and VEGF mRNAs. Western blot analysis was used to measure the levels of HIF-1α and VEGF proteins. Although the small amount of HIF-1α protein was able to be detected in high glucose group but not in control group, there was no significant difference between the expression of HIF-1α mRNA of RPE cells in high glucose group and that of RPE cells in control group. As compared with RPE cells in control group, the mRNA expression and the protein synthesis of VEGF in high glucose group were up-regulated. As compared with RPE cells in hypoxic group, the expression of HIF-1α mRNA of RPE cells in combination group was not different, but the protein synthesis of HIF-1α, the mRNA expression and the protein synthesis of VEGF were more obviously up-regulated. In conclusion, high concentration glucose mainly influence the protein synthesis of HIF-1α of RPE cell, and HIF-1α protein is able to be accumulated in high concentration glucose. Under hypoxia, the HIF-1α protein induced by high concentration glucose is more stable, and the expression of VEGF is obviously increased. It is suggested that high concentration glucose may play a role in retinal neovascularization, especially at ischemia stage of diabetic retinopathy.展开更多
文摘BACKGROUND Synaptotagmins(SYTs)are a family of 17 membrane transporters that function as calcium ion sensors during the release of Ca2+-dependent neurotransmitters and hormones.However,few studies have reported whether members of the SYT family play a role in glucose uptake in diabetic retinopathy(DR)through Ca2+/glucose transporter-1(GLUT1)and the possible regulatory mechanism of SYTs.AIM To elucidate the role of the SYT family in the regulation of glucose transport in retinal pigment epithelial cells and explore its potential as a therapeutic target for the clinical management of DR.METHODS DR was induced by streptozotocin in C57BL/6J mice and by high glucose medium in human retinal pigment epithelial cells(ARPE-19).Bioinformatics analysis,reverse transcriptase-polymerase chain reaction,Western blot,flow cytometry,ELISA,HE staining,and TUNEL staining were used for analysis.RESULTS Six differentially expressed proteins(SYT2,SYT3,SYT4,SYT7,SYT11,and SYT13)were found between the DR and control groups,and SYT4 was highly expressed.Hyperglycemia induces SYT4 overexpression,manipulates Ca2+influx to induce GLUT1 fusion with the plasma membrane,promotes abnormal expression of the glucose transporter GLUT1 and excessive glucose uptake,induces ARPE-19 cell apoptosis,and promotes DR progression.Parkin deficiency inhibits the proteasomal degradation of SYT4 in DR,resulting in SYT4 accumulation and enhanced GLUT1 fusion with the plasma membrane,and these effects were blocked by oe-Parkin treatment.Moreover,dysregulation of the myelin transcription factor 1(Myt1)-induced transcription of SYT4 in DR further activated the SYT4-mediated stimulus-secretion coupling process,and this process was inhibited in the oe-MYT1-treated group.CONCLUSION Our study reveals the key role of SYT4 in regulating glucose transport in retinal pigment epithelial cells during the pathogenesis of DR and the underlying mechanism and suggests potential therapeutic targets for clinical DR.
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Managing diabetes during pregnancy is challenging,given the significant risk it poses for both maternal and foetal health outcomes.While traditional methods involve capillary self-monitoring of blood glucose level monitoring and periodic HbA1c tests,the advent of continuous glucose monitoring(CGM)systems has revolutionized the approach.These devices offer a safe and reliable means of tracking glucose levels in real-time,benefiting both women with diabetes during pregnancy and the healthcare providers.Moreover,CGM systems have shown a low rate of side effects and high feasibility when used in pregnancies complicated by diabetes,especially when paired with continuous subcutaneous insulin infusion pump as hybrid closed loop device.Such a combined approach has been demonstrated to improve overall blood sugar control,lessen the occurrence of preeclampsia and neonatal hypoglycaemia,and minimize the duration of neonatal intensive care unit stays.This paper aims to offer a comprehensive evaluation of CGM metrics specifically tailored for pregnancies impacted by type 1 diabetes mellitus.
基金Supported by Medical and Health Science and Technology Project of Zhejiang Province(No.2023KY1356).
文摘AIM:To evaluate the effects of LIN28A(human)on high glucose-induced retinal pigmented epithelium(RPE)cell injury and its possible mechanism.METHODS:Diabetic retinopathy model was generated following 48h of exposure to 30 mmol/L high glucose(HG)in ARPE-19 cells.Quantitative real-time polymerase chain reaction(qRT-PCR)and Western blot tested the expression of the corresponding genes and proteins.Cell viability as well as apoptosis was determined through cell counting kit-8(CCK-8)and flow cytometry assays.Immunofluorescence assay was adopted to evaluate autophagy activity.Caspase 3 activity,oxidative stress markers,and cytokines were appraised adopting their commercial kits,respectively.Finally,ARPE-19 cells were preincubated with EX527,a Sirtuin 1(SIRT1)inhibitor,prior to HG stimulation to validate the regulatory mechanism.RESULTS:LIN28A was downregulated in HG-challenged ARPE-19 cells.LIN28A overexpression greatly inhibited HGinduced ARPE-19 cell viability loss,apoptosis,oxidative damage as well as inflammatory response.Meanwhile,the repressed autophagy and SIRT1 in ARPE-19 cells challenged with HG were elevated after LIN28A overexpression.In addition,treatment of EX527 greatly inhibited the activated autophagy following LIN28A overexpression and partly abolished the protective role of LIN28A against HG-elicited apoptosis,oxidative damage as well as inflammation in ARPE-19 cells.CONCLUSION:LIN28A exerts a protective role against HG-elicited RPE oxidative damage,inflammation,as well as apoptosis via regulating SIRT1/autophagy.
基金supported by the National Natural Science Foundation of China(No.32071713)the Outstanding Youth Foundation Project of Heilongjiang Province of China(JQ2019C001)。
文摘The global commitment to pivoting to sustainable energy and products calls for technology development to utilize solar energy for hydrogen(H_(2))and value-added chemicals production by biomass photoreforming.Herein,a novel dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction has been the production of lactic acid with high-yield and H_(2)with high-efficiency by selective glucose photoreforming.The optimized Zn_(0.3)Cd_(0.7)S exhibits outstanding H_(2)generation(13.64 mmol h^(-1)g^(-1)),glucose conversion(96.40%),and lactic acid yield(76.80%),over 272.80 and 19.21 times higher than that of bare ZnS(0.05 mmol h^(-1)g^(-1))and CdS(0.71 mmol h^(-1)g^(-1))in H_(2)generation,respectively.The marigold-like morphology provides abundant active sites and sufficient substrates accessibility for the photocatalyst,while the specific role of the homojunction formed by hexagonal wurtzite(WZ)and cubic zinc blende(ZB)in photoreforming biomass has been demonstrated by density functional theory(DFT)calculations.Glucose is converted to lactic acid on the WZ surface of Zn_(0.3)Cd_(0.7)S via the photoactive species·O_(2)^(-),while the H_(2)is evolved from protons(H^(+))in H_(2)O on the ZB surface of Zn_(0.3)Cd_(0.7)S.This work paves a promising road for the production of sustainable energy and products by integrating photocatalysis and biorefine.
基金National Natural Science Foundation of China,No.82060161,81960154,and 81760156Jiangxi Provincial Youth Science Foundation,No.2018ACB21040+1 种基金Natural Science Foundation of Jiangxi Province,No.20212BAB206020and Foundation of Health commission of Jiangxi Province,No.SKJP220225830.
文摘BACKGROUND The small intestine is known to play a crucial role in the development and remission of diabetes mellitus(DM).However,the exact mechanism by which mid-small intestinal bypass improves glucose metabolism in diabetic rats is not fully understood.AIM To elucidate the mechanisms by which mid-small intestinal bypass improves glucose metabolism.METHODS Streptozotocin(STZ)was used to induce DM in Sprague-Dawley(SD)rats at a dose of 60 mg/kg.The rats were then randomly divided into two groups:The mid-small intestine bypass(MSIB)group and the sham group(underwent switch laparotomy).Following a 6-wk recovery period post-surgery,the rats underwent various assessments,including metabolic parameter testing,analysis of liver glycogen levels,measurement of key gluconeogenic enzyme activity,characterization of the gut microbiota composition,evaluation of hormone levels,determination of bile acid concentrations,and assessment of the expression of the intestinal receptors Takeda G protein-coupled receptor 5 and farnesoid X receptor.RESULTS The MSIB group of rats demonstrated improved glucose metabolism and lipid metabolism,along with increased hepatic glycogen content.Furthermore,there was a decrease in the expression of the key gluconeogenic enzymes phosphoenolpyruvate carboxykinase 1 and glucose-6-phosphatase.Importantly,the MSIB group exhibited a substantial increase in the abundances of intestinal Lactobacillus,Clostridium symbiosum,Ruminococcus gnavus,and Bilophila.Moreover,higher levels of secondary bile acids,such as intestinal lithocholic acid,were observed in this group.Remarkably,the changes in the gut microbiota showed a significant correlation with the expression of key gluconeogenic enzymes and glucagon-like peptide 1(GLP-1)at 6 wk postoperatively,highlighting their potential role in glucose regulation.These findings highlight the beneficial effects of mid-small intestine bypass on glucose metabolism and the associated modulation of the gut microbiota.CONCLUSION The findings of this study demonstrate that the introduction of postoperative intestinal Clostridium symbiosum in the mid-small intestine contributes to the enhancement of glucose metabolism in nonobese diabetic rats.This improvement is attributed to the increased inhibition of hepatic gluconeogenesis mediated by GLP-1,resulting in a favorable modulation of glucose homeostasis.
文摘Objective:To explore the regulatory mechanism of transient receptor potential melastatin-7(TRPM7)in high glucose-induced renal tubular epithelial cell injury.Methods:The expression of TRPM7 in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells was detected by RT-qPCR.Then,the TRPM7 interference vector was constructed,and the downstream high mobility group box 1(HMGB1)/Toll-like receptor 4(TLR4)signaling pathway proteins were detected.Next,in addition to interference with TRPM7 expression,overexpression of HMGB1 in high glucose-induced HK-2 cells was performed.Cell activity,apoptosis,oxidative stress levels,and inflammation levels were determined by CCK8,TUNEL,Western blotting,immunofluorescence and related kits.Results:TRPM7 expression was upregulated in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells.Interference with TRPM7 reduced cell damage,epithelial-mesenchymal transition,oxidative stress,and inflammatory response in high glucose-induced HK-2 cells via inhibiting the HMGB1/TLR4 signaling pathway.However,the effects induced by TRPM7 silencing were abrogated by HMGB1 overexpression.Conclusions:Decreased TRPM7 alleviates high glucose-induced renal tubular epithelial cell injury by inhibiting the HMGB1/TLR4 signaling pathway.Further animal experiments and clinical trials are warranted to verify its effect.
基金the Clinical Research and Cultivation Plan Project of the Second Affiliated Hospital of Anhui Medical University,No.2021LCYB17.
文摘BACKGROUND Currently,the lack of comparative studies between weekly and daily formulations of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for glucose excursion is worth investigation.AIM To investigate the effects of weekly and daily formulations of GLP-1RA on glucose excursion and inflammation in overweight and obese patients with type 2 diabetes.METHODS Seventy patients with type 2 diabetes mellitus who were treated at our hospital between January 2019 and January 2022 were enrolled in this retrospective analysis.All patients were treated with metformin.We evaluated changes in blood glucose levels and a series of important indicators in patients before and after treatment with either a weekly or daily preparation of GLP-1RA(group A;n=33 and group B;n=37).RESULTS The degree of decrease in the levels of fasting blood glucose,mean blood glucose,mean amplitude of glycemic excursions,total cholesterol,triglycerides,tumor necrosis factor-α,interleukin-6,and high-sensitivity C-reactive protein after treatment in group A was higher than that in group B(P<0.05),whereas the 2-h postprandial blood glucose levels decreased more so in group B than in group A(P<0.001).However,there were no statistically significant differences in the levels of glycated hemoglobin,standard deviation of blood glucose,coefficient of variation,absolute mean of daily differences,percentage of time with 3.9 mmol/L<glucose<10 mmol/L,and high-and low-density lipoproteins between the two groups(P>0.05).The incidence of adverse reactions was significantly lower in group A than in group B(P<0.05).CONCLUSION The effect of the weekly preparation of GLP-1RA in controlling blood glucose levels in the patients,suppressing inflammation,and reducing adverse reactions was significantly higher than that of the daily preparations,which is worthy of clinical promotion.
基金supported by the National Natural Science foundation of China(No.31071531)the Scientific Research Fund of the Hunan Provincial Education Department(No.14A071)the China National Tobacco Corp Hunan Branch(15-17Aa04)
文摘Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC),high-fat diet(HFD),HFD with low-dose CGA(20 mg/kg,HFD-LC),and HFD with high-dose CGA(90 mg/kg,HFD-HC).The oral glucose tolerance test was performed,and fast serum insulin(FSI)was detected using an enzyme-linked immunosorbent assay.The m RNA expression levels of glucose transporters(Sglt-1 and Glut-2)and proglucagon(Plg)in different intestinal segments(the duodenum,jejunum,ileum,and colon)were analyzed using quantitative real-time polymerase chain reaction.SGLT-1 protein and the morphology of epithelial cells in the duodenum and jejunum was localized by using immunofluorescence.Results At both doses,CGA ameliorated the HFD-induced body weight gain,maintained FSI,and increased postprandial 30-min glucagon-like peptide 1 secretion.High-dose CGA inhibited the HFD-induced elevation in Sglt-1 expression.Both CGA doses normalized the HFD-induced downregulation of Glut-2 and elevated the expression of Plg in all four intestinal segments.Conclusion An HFD can cause a glucose metabolism disorder in the rat intestine and affect body glucose homeostasis.CGA can modify intestinal glucose metabolism by regulating the expression of intestinal glucose transporters and Plg,thereby controlling the levels of blood glucose and insulin to maintain glucose homeostasis.
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National Natural Science Foundation of China(81660599)Foundation of Zunyi Medical University (2013F-686+1 种基金2013F-738)Postgraduate Education Foundation of Guizhou Province(KYJJ2017008).
文摘OBJECTIVE To investigate the protective effect of icariin(ICA) on learning and memory function in APP/PS1/Tau triple transgenic Alzheimer disease mice(3×Tg-AD mice),and then to explore whether its mechanism is related to the improvement of brain glucose metabolism disorder.METHODS Three-month-old male 3 ×Tg-AD mice were randomly divided into three groups(n=10):3×Tg group,3×Tg+ICA low-dose group(30 mg·kg-1) and 3×Tg + ICA high-dose group(60 mg·kg-1).Age-matched male wild type(WT) mice were randomly divided into two groups(n=10):WT control group and WT+ICA60 mg·kg-1 group.ICA in vehicle(0.5% Tween-80 in distilled water) was given orally once a day for five months in the 3×Tg+ICA groups.3×Tg and WT control group were given an equal volume vehicle.Morris water maze was used to detect the learning and memory function of mice.Brain glucose metabolism in 3×Tg mice was observed by 18 F-FDG microPET imaging technique.Nissl staining and HE staining were used to evaluate the survival neurons in hippocampus of mice.Glucose oxidase assay was used to detect glucose contents in cortex of mice.The protein expression of APP,Aβ1-40,Aβ1-42 and glucose transporter 1(GLUT1),and the phosphorylation level of tau protein at multiple sites in hippocampus were detected by Western blotting.RESULTS Behavioral examination revealed a profound decrease learning and memory function,accompanied by a decrease in number of neuronal cells in 3×Tg-AD mice.Moreover,the cerebral18 F-FDG uptake rate per gram tissue was reduced and the glucose contents in the cortex were increased in 3×Tg-AD mice.In addition,Western blotting analysis showed that the expression of APP,Aβ1-40,Aβ1-42 proteins and the levels of tau protein phosphorylation at Ser199/202 and PHF-1(Ser396/404) sites were increased significantly,followed by a decrease of GLUT1 expression in hippocampus of 3×Tg-AD mice.All of these changes in behavioral functions,neuronal loss and related protein expression were reversed when mice were treated with ICA.CONCLUSION ICA can improve the learning and memory ability of AD model mice,the mechanism may be related to the improvement of cerebral glucose metabolism dysfunction by increasing the expression of GLUT1.
基金a grant from the National Natural Sciences Foundation of China (No. 30600810)
文摘The role of serum and glucocorticoid-induced kinase 1 (SGK1) pathway in the connective tissue growth factor (CTGF) expression was investigated in cultured human mesangial cells (HMCs) under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 (SD) could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP (FP) under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 (KN) could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.
文摘Summary: In order to explore the effect of high glucose concentration and high glucose concentration with hypoxia on the production of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF), human RPE cells were cultured in 5,56 mmol/L glucose (control group), 5.56 mmol/L glucose with 150 !a mol/L COCl2 (hypoxic group), 25 mmol/L glucose (high glucose group) and 25 mmol/L glucose with 150 μmol/L COCl2 (combination group). RT-PCR was used to detect the expression of HIF-1α and VEGF mRNAs. Western blot analysis was used to measure the levels of HIF-1α and VEGF proteins. Although the small amount of HIF-1α protein was able to be detected in high glucose group but not in control group, there was no significant difference between the expression of HIF-1α mRNA of RPE cells in high glucose group and that of RPE cells in control group. As compared with RPE cells in control group, the mRNA expression and the protein synthesis of VEGF in high glucose group were up-regulated. As compared with RPE cells in hypoxic group, the expression of HIF-1α mRNA of RPE cells in combination group was not different, but the protein synthesis of HIF-1α, the mRNA expression and the protein synthesis of VEGF were more obviously up-regulated. In conclusion, high concentration glucose mainly influence the protein synthesis of HIF-1α of RPE cell, and HIF-1α protein is able to be accumulated in high concentration glucose. Under hypoxia, the HIF-1α protein induced by high concentration glucose is more stable, and the expression of VEGF is obviously increased. It is suggested that high concentration glucose may play a role in retinal neovascularization, especially at ischemia stage of diabetic retinopathy.