BACKGROUND Mesenchymal stem cells(MSCs)are a type of stem cells that possess relevant regenerative abilities and can be used to treat many chronic diseases.Diabetes mellitus(DM)is a frequently diagnosed chronic diseas...BACKGROUND Mesenchymal stem cells(MSCs)are a type of stem cells that possess relevant regenerative abilities and can be used to treat many chronic diseases.Diabetes mellitus(DM)is a frequently diagnosed chronic disease characterized by hyperglycemia which initiates many multisystem complications in the long-run.DM patients can benefit from MSCs transplantation to curb down the pathological consequences associated with hyperglycemia persistence and restore the function of damaged tissues.MSCs therapeutic outcomes are found to last for short period of time and ultimately these regenerative cells are eradicated and died in DM disease model.AIM To investigate the impact of high glucose or hyperglycemia on the cellular and molecular characteristics of MSCs.METHODS Human adipose tissue-derived MSCs(hAD-MSCs)were seeded in low(5.6 mmol/L of glucose)and high glucose(25 mmol/L of glucose)for 7 d.Cytotoxicity,viability,mitochondrial dynamics,and apoptosis were deplored using specific kits.Western blotting was performed to measure the protein expression of phosphatidylinositol 3-kinase(PI3K),TSC1,and mammalian target of rapamycin(mTOR)in these cells.RESULTS hAD-MSCs cultured in high glucose for 7 d demonstrated marked decrease in their viability,as shown by a significant increase in lactate dehydrogenase(P<0.01)and a significant decrease in Trypan blue(P<0.05)in these cells compared to low glucose control.Mitochondrial membrane potential,indicated by tetramethylrhodamine ethyl ester(TMRE)fluorescence intensity,and nicotinamide adenine dinucleotide(NAD+)/NADH ratio were significantly dropped(P<0.05 for TMRE and P<0.01 for NAD+/NADH)in high glucose exposed hAD-MSCs,indicating disturbed mitochondrial function.PI3K protein expression significantly decreased in high glucose culture MSCs(P<0.05 compared to low glucose)and it was coupled with significant upregulation in TSC1(P<0.05)and downregulation in mTOR protein expression(P<0.05).Mitochondrial complexes I,IV,and V were downregulated profoundly in high glucose(P<0.05 compared 展开更多
BACKGROUND Gastric cancer(GC)is a common malignant tumor with high incidence and mortality rates globally,especially in East Asian countries.Helicobacter pylori(H.pylori)infection is a significant and independent risk...BACKGROUND Gastric cancer(GC)is a common malignant tumor with high incidence and mortality rates globally,especially in East Asian countries.Helicobacter pylori(H.pylori)infection is a significant and independent risk factor for GC.However,its underlying mechanism of action is not fully understood.Dickkopf-related protein(DKK)1 is a Wnt signaling antagonist,and cytoskeleton-associated protein(CKAP)4 is a newly identified DKK1 receptor.Recent studies found that the binding of DKK1 to CAKP4 mediated the procancer signaling of DKK1 independent of Wnt signaling.We hypothesize that H.pylori-induced activation of DKK1/CKAP4 signaling contributes to the initiation and progression of GC.AIM To investigate the interaction of H.pylori infection,DKK1 and CAKP4 in GC,as well as the underlying molecular mechanisms.METHODS RNA sequencing was used to identify differentially expressed genes(DEGs)between H.pylori-infected and uninfected primary GC cells.Gain-and loss-offunction experiments were performed to verify the H.pylori-induced upregulation of activator protein-1(AP-1)in GC cells.A dual-luciferase reporter assay and co-immunoprecipitation were used to determine the binding of AP-1 to the DKK1 promoter and DKK1 to CKAP4.Western blotting and immunohistochemistry detected the expression of DKK1,CKAP4,and phosphatidylinositol 3-kinase(PI3K)pathway-related proteins in GC cells and tissues.Functional experiments and tumorigenicity in nude mice detected malignant behavior of GC cells in vitro and in vivo.RESULTS We identified 32 DEGs between primary GC cells with and without H.pylori infection,including JUN,fos-like antigen-1(FOSL1),and DKK1,and confirmed that the three proteins and CKAP4 were highly expressed in H.pylori-infected GC cells,H.pylori-infected gerbil gastric tissues,and human GC tissues.JUN and FOSL1 form AP-1 to transcriptionally activate DKK1 expression by binding to the DKK1 promoter.Activated DKK1 bound to CKAP4,but not the most common Wnt coreceptor low-density lipoprotein receptor-related protein 5/6,to promot展开更多
The study was conducted to investigate the effect and mechanism of dietary quercetin supplementation on protein utilization of Arbor Acres(AA)broilers.A total of 2401-day-old AA broilers were randomly allocated to fou...The study was conducted to investigate the effect and mechanism of dietary quercetin supplementation on protein utilization of Arbor Acres(AA)broilers.A total of 2401-day-old AA broilers were randomly allocated to four treatments with six replicates,comprising 10 broilers each replicate(60 broilers per treatment).Birds were fed either a corn-soybean meal basal diet without quercetin(control)or a basal diet supplemented with 0.2,0.4 or 0.6 g of quercetin per kg feed,and the trial lasted 42 days.Dietary quercetin supplementation tended to increase the apparent metabolic rate of protein(p=0.076)and the content of serum albumin(p=0.062)in AA broilers.Compared with the control,dietary quercetin supplementation increased the contents of protein in breast muscle(p<0.05)and in thigh muscle(p=0.053).In addition,quercetin up-regulated mRNA expression of insulin-like growth factor 1(IGF-1),phosphatidylinositol 3-kinase(PI3K),target of rapamycin(TOR),ribosomal protein S6 kinase 1(S6K1),eukaryotic translation initiation factor 4E(eIF4E),eukaryotic translation initiation factor 4G(eIF4G),eukaryotic elongation factor 2(eEF2)and eukaryotic translation initiation factor 4B(eIF4B)genes and down-regulated mRNA expression of eukaryotic elongation factor 2 kinase(eEF2K)and eukaryotic initiation factor 4E binding protein1(4E-BP1)genes in breast muscle,thigh muscle and liver of AA broilers(p<0.05).The present results suggested that dietary quercetin supplementation enhanced protein utilization in broilers by activating TOR signaling pathway.展开更多
AIM:To explore expressions of PIK3CA in the progression of gastric cancer from primary to metastasis and its effects on activation of phosphatidylinositol 3-kinase(PI3K)/Akt pathway.METHODS:mRNA and protein levels of ...AIM:To explore expressions of PIK3CA in the progression of gastric cancer from primary to metastasis and its effects on activation of phosphatidylinositol 3-kinase(PI3K)/Akt pathway.METHODS:mRNA and protein levels of PIK3CA were assessed,respectively,by real-time quantitative polymerase chain reaction and immunohistochemistry in specimens of normal gastric mucosa,primary foci and lymph node and distant metastasis of gastric cancer.Akt and phosphorylated Akt protein were also examined by Western blotting in these tissues,in order to analyze the effect of PIK3CA expression level changes on the activation of PI3K/Akt signaling pathway.RESULTS:PIK3CA mRNA in lymph node metastasis were approximately 5 and 2 folds higher,respectively,than that in the corresponding normal gastric mucosa and primary gastric cancer tissues(P<0.05),while no statistical significance was found compared with distant metastasis.Immunohistochemically,PIK3CA protein expression was discovered in 7(35%)specimens of 20 primary foci vs 10(67%)of 15 of lymph node metastasis or 11(61%)of 18 of distant metastasis(35%vs 67%,P=0.015;35%vs 61%,P=0.044).With the increased level of PIK3CA expression,the total Akt protein expression remained almost unchanged,but p-Akt protein was upregulated markedly.CONCLUSION:Increased expression of PIK3CA is expected to be a promising indicator of metastasis in gastric cancer.Up-regulation of PIK3CA may promote the metastasis of gastric cancer through aberrant activation of PI3K/Akt signaling.展开更多
文摘BACKGROUND Mesenchymal stem cells(MSCs)are a type of stem cells that possess relevant regenerative abilities and can be used to treat many chronic diseases.Diabetes mellitus(DM)is a frequently diagnosed chronic disease characterized by hyperglycemia which initiates many multisystem complications in the long-run.DM patients can benefit from MSCs transplantation to curb down the pathological consequences associated with hyperglycemia persistence and restore the function of damaged tissues.MSCs therapeutic outcomes are found to last for short period of time and ultimately these regenerative cells are eradicated and died in DM disease model.AIM To investigate the impact of high glucose or hyperglycemia on the cellular and molecular characteristics of MSCs.METHODS Human adipose tissue-derived MSCs(hAD-MSCs)were seeded in low(5.6 mmol/L of glucose)and high glucose(25 mmol/L of glucose)for 7 d.Cytotoxicity,viability,mitochondrial dynamics,and apoptosis were deplored using specific kits.Western blotting was performed to measure the protein expression of phosphatidylinositol 3-kinase(PI3K),TSC1,and mammalian target of rapamycin(mTOR)in these cells.RESULTS hAD-MSCs cultured in high glucose for 7 d demonstrated marked decrease in their viability,as shown by a significant increase in lactate dehydrogenase(P<0.01)and a significant decrease in Trypan blue(P<0.05)in these cells compared to low glucose control.Mitochondrial membrane potential,indicated by tetramethylrhodamine ethyl ester(TMRE)fluorescence intensity,and nicotinamide adenine dinucleotide(NAD+)/NADH ratio were significantly dropped(P<0.05 for TMRE and P<0.01 for NAD+/NADH)in high glucose exposed hAD-MSCs,indicating disturbed mitochondrial function.PI3K protein expression significantly decreased in high glucose culture MSCs(P<0.05 compared to low glucose)and it was coupled with significant upregulation in TSC1(P<0.05)and downregulation in mTOR protein expression(P<0.05).Mitochondrial complexes I,IV,and V were downregulated profoundly in high glucose(P<0.05 compared
基金the National Natural Science Foundation of China,No.32160166,No.31760328,and No.31960028Natural Science Foundation of Guizhou Province,No.ZC[2020]4Y026,No.JC[2020]1Z010,No.JC[2020]1Y333,and No.ZK[2022]041Scientific Research Project of Guizhou Medical University,No.20NSP068.
文摘BACKGROUND Gastric cancer(GC)is a common malignant tumor with high incidence and mortality rates globally,especially in East Asian countries.Helicobacter pylori(H.pylori)infection is a significant and independent risk factor for GC.However,its underlying mechanism of action is not fully understood.Dickkopf-related protein(DKK)1 is a Wnt signaling antagonist,and cytoskeleton-associated protein(CKAP)4 is a newly identified DKK1 receptor.Recent studies found that the binding of DKK1 to CAKP4 mediated the procancer signaling of DKK1 independent of Wnt signaling.We hypothesize that H.pylori-induced activation of DKK1/CKAP4 signaling contributes to the initiation and progression of GC.AIM To investigate the interaction of H.pylori infection,DKK1 and CAKP4 in GC,as well as the underlying molecular mechanisms.METHODS RNA sequencing was used to identify differentially expressed genes(DEGs)between H.pylori-infected and uninfected primary GC cells.Gain-and loss-offunction experiments were performed to verify the H.pylori-induced upregulation of activator protein-1(AP-1)in GC cells.A dual-luciferase reporter assay and co-immunoprecipitation were used to determine the binding of AP-1 to the DKK1 promoter and DKK1 to CKAP4.Western blotting and immunohistochemistry detected the expression of DKK1,CKAP4,and phosphatidylinositol 3-kinase(PI3K)pathway-related proteins in GC cells and tissues.Functional experiments and tumorigenicity in nude mice detected malignant behavior of GC cells in vitro and in vivo.RESULTS We identified 32 DEGs between primary GC cells with and without H.pylori infection,including JUN,fos-like antigen-1(FOSL1),and DKK1,and confirmed that the three proteins and CKAP4 were highly expressed in H.pylori-infected GC cells,H.pylori-infected gerbil gastric tissues,and human GC tissues.JUN and FOSL1 form AP-1 to transcriptionally activate DKK1 expression by binding to the DKK1 promoter.Activated DKK1 bound to CKAP4,but not the most common Wnt coreceptor low-density lipoprotein receptor-related protein 5/6,to promot
基金Supported by the National Natural Science Foundation of China(31872377)。
文摘The study was conducted to investigate the effect and mechanism of dietary quercetin supplementation on protein utilization of Arbor Acres(AA)broilers.A total of 2401-day-old AA broilers were randomly allocated to four treatments with six replicates,comprising 10 broilers each replicate(60 broilers per treatment).Birds were fed either a corn-soybean meal basal diet without quercetin(control)or a basal diet supplemented with 0.2,0.4 or 0.6 g of quercetin per kg feed,and the trial lasted 42 days.Dietary quercetin supplementation tended to increase the apparent metabolic rate of protein(p=0.076)and the content of serum albumin(p=0.062)in AA broilers.Compared with the control,dietary quercetin supplementation increased the contents of protein in breast muscle(p<0.05)and in thigh muscle(p=0.053).In addition,quercetin up-regulated mRNA expression of insulin-like growth factor 1(IGF-1),phosphatidylinositol 3-kinase(PI3K),target of rapamycin(TOR),ribosomal protein S6 kinase 1(S6K1),eukaryotic translation initiation factor 4E(eIF4E),eukaryotic translation initiation factor 4G(eIF4G),eukaryotic elongation factor 2(eEF2)and eukaryotic translation initiation factor 4B(eIF4B)genes and down-regulated mRNA expression of eukaryotic elongation factor 2 kinase(eEF2K)and eukaryotic initiation factor 4E binding protein1(4E-BP1)genes in breast muscle,thigh muscle and liver of AA broilers(p<0.05).The present results suggested that dietary quercetin supplementation enhanced protein utilization in broilers by activating TOR signaling pathway.
基金Supported by Medical Research Fund of Guangdong Province,No.A2007284Health Bureau Fund of Guangzhou,No.2009-YB-169
文摘AIM:To explore expressions of PIK3CA in the progression of gastric cancer from primary to metastasis and its effects on activation of phosphatidylinositol 3-kinase(PI3K)/Akt pathway.METHODS:mRNA and protein levels of PIK3CA were assessed,respectively,by real-time quantitative polymerase chain reaction and immunohistochemistry in specimens of normal gastric mucosa,primary foci and lymph node and distant metastasis of gastric cancer.Akt and phosphorylated Akt protein were also examined by Western blotting in these tissues,in order to analyze the effect of PIK3CA expression level changes on the activation of PI3K/Akt signaling pathway.RESULTS:PIK3CA mRNA in lymph node metastasis were approximately 5 and 2 folds higher,respectively,than that in the corresponding normal gastric mucosa and primary gastric cancer tissues(P<0.05),while no statistical significance was found compared with distant metastasis.Immunohistochemically,PIK3CA protein expression was discovered in 7(35%)specimens of 20 primary foci vs 10(67%)of 15 of lymph node metastasis or 11(61%)of 18 of distant metastasis(35%vs 67%,P=0.015;35%vs 61%,P=0.044).With the increased level of PIK3CA expression,the total Akt protein expression remained almost unchanged,but p-Akt protein was upregulated markedly.CONCLUSION:Increased expression of PIK3CA is expected to be a promising indicator of metastasis in gastric cancer.Up-regulation of PIK3CA may promote the metastasis of gastric cancer through aberrant activation of PI3K/Akt signaling.
