In our previous study, the specific interaction between P-factor, a peptide pheromone and its receptor, Mam2, on the cell surface of the fission yeast Schizosaccharomyces pombe was investigated by two methods, an atom...In our previous study, the specific interaction between P-factor, a peptide pheromone and its receptor, Mam2, on the cell surface of the fission yeast Schizosaccharomyces pombe was investigated by two methods, an atomic force microscope (AFM) and a GFP reporter assay. The removal of Leu at C-terminal of P-factor resulted in an inactivation of P-factor function to bind Mam2 and induce the signal transduction pathway. Here, we used truncated P-factor derivatives lacking N-terminal of P-factor (P12 ~ P22: 12 ~ 22 amino acid residues from C-terminal) as ligands for Mam2. From the dose-dependent analysis of the GFP reporter assay ranging from 1 nM to 100 μM of the peptide concentration, the peptides can be classified into three groups based on EC50 and maximal GFP production level, group1 (P-factor), group2 (P17 ~ 22), and group3 (P12 ~ P16). At 0.1 μM, only P-factor induced the signal transduction pathway. At 1 μM, peptides from group2 partially induced the pathway and peptides from group3 induced the pathway a little. At 10 μM, all peptides induced the pathway mostly depending on the length of peptides. We also performed AFM experiments using P-factor and peptides from group3 to investigate the interaction between the peptides and Mam2 for comparison between the two methods.展开更多
In this study, we aimed to identify starter strains of lactic acid bacteria (LAB) to produce soymilk yogurt that can decrease the risk of diabetes mellitus (DM) and its complications. The inhibition assays of the dipe...In this study, we aimed to identify starter strains of lactic acid bacteria (LAB) to produce soymilk yogurt that can decrease the risk of diabetes mellitus (DM) and its complications. The inhibition assays of the dipeptidyl peptidase IV (DPP- IV) and advanced glycation end products (AGEs) formation were conducted using 70% ethanol (EtOH) extraction of freeze-dried soymilk yogurt. Soymilk yogurt produced using Weissella confusa TOKAI 2 showed the highest inhibition rate in the α-amylase inhibition assay, while soymilk yogurt produced using Lactiplantibacillus plantarum TOKAI 17 showed the highest inhibition rates in the α-glucosidase and DPP-Ⅳ inhibition assays, respectively. Soymilk yogurt produced using Streptococcus macedonicus TOKAI 4 showed the highest inhibitory activities in Nω-(carboxymethyl) arginine (CMA) and Nε-(carboxymethyl) lysine (CML) formation, respectively. Furthermore, soymilk yogurt prepared using Lb. plantarum TOKAI 17 and Lactiplantibacillus pentosus TOKAI 35 exhibited higher proportions of aglycone isoflavones than soymilk and showed a higher fluorescent AGEs inhibitory activity than that of soymilk (p < 0.05). Interestingly, the inhibition assay assessing fluorescent AGEs formation using isoflavones indicated that aglycone-type isoflavones, such as genistein and daidzein, had higher inhibitory activities than that of glycosides (p < 0.05). These results indicate that soymilk yogurt produced using Lb. plantarum TOKAI 17 and Lb. pentosus TOKAI 35 had inhibitory effects on α-glucosidase, DPP-Ⅳ, and AGEs formation in vitro, and that aglycone isoflavones might inhibit the formation of fluorescent AGEs.展开更多
Alterations in cellular metabolism may contribute to tumor proliferation and survival.Upregulation of the facilitative glucose transporter(GLUT)plays a key role in promoting cancer.GLUT5 mediates modulation of fructos...Alterations in cellular metabolism may contribute to tumor proliferation and survival.Upregulation of the facilitative glucose transporter(GLUT)plays a key role in promoting cancer.GLUT5 mediates modulation of fructose utilization,and its overexpression has been associated with poor prognosis in several cancers.However,its metabolic regulation remains poorly understood.Here,we demonstrated elevated GLUT5 expression in human cholangiocarcinoma(CCA),using RNA sequencing data from samples of human tissues and cell lines,as compared to normal liver tissues or a cholangiocyte cell line.Cells exhibiting highexpression of GLUT5 showed increased rates of cell proliferation and ATP production,particularly in a fructose-supplemented medium.In contrast,GLUT5 silencing attenuated cell proliferation,ATP production,cell migration/invasion,and improved epithelialemesenchymal transition(EMT)balance.Correspondingly,fructose consumption increased tumor growth in a nude mouse xenograft model,and GLUT5 silencing suppressed growth,supporting the tumor-inhibitory effect of GLUT5 downregulation.Furthermore,in the metabolic pathways of fructolysis-Warburg effect,the expression levels of relative downstream genes,including ketohexokinase(KHK),aldolase B(ALDOB),lactate dehydrogenase A(LDHA),and monocarboxylate transporter 4(MCT4),as well as hypoxia-inducible factor 1 alpha(HIF1A),were altered in a GLUT5 expression-dependent manner.Taken together,these findings indicate that GLUT5 could be a potential target for CCA therapeutic approach via metabolic regulation.展开更多
文摘In our previous study, the specific interaction between P-factor, a peptide pheromone and its receptor, Mam2, on the cell surface of the fission yeast Schizosaccharomyces pombe was investigated by two methods, an atomic force microscope (AFM) and a GFP reporter assay. The removal of Leu at C-terminal of P-factor resulted in an inactivation of P-factor function to bind Mam2 and induce the signal transduction pathway. Here, we used truncated P-factor derivatives lacking N-terminal of P-factor (P12 ~ P22: 12 ~ 22 amino acid residues from C-terminal) as ligands for Mam2. From the dose-dependent analysis of the GFP reporter assay ranging from 1 nM to 100 μM of the peptide concentration, the peptides can be classified into three groups based on EC50 and maximal GFP production level, group1 (P-factor), group2 (P17 ~ 22), and group3 (P12 ~ P16). At 0.1 μM, only P-factor induced the signal transduction pathway. At 1 μM, peptides from group2 partially induced the pathway and peptides from group3 induced the pathway a little. At 10 μM, all peptides induced the pathway mostly depending on the length of peptides. We also performed AFM experiments using P-factor and peptides from group3 to investigate the interaction between the peptides and Mam2 for comparison between the two methods.
基金supported by a grant from the Tokai University and Probio LLC.
文摘In this study, we aimed to identify starter strains of lactic acid bacteria (LAB) to produce soymilk yogurt that can decrease the risk of diabetes mellitus (DM) and its complications. The inhibition assays of the dipeptidyl peptidase IV (DPP- IV) and advanced glycation end products (AGEs) formation were conducted using 70% ethanol (EtOH) extraction of freeze-dried soymilk yogurt. Soymilk yogurt produced using Weissella confusa TOKAI 2 showed the highest inhibition rate in the α-amylase inhibition assay, while soymilk yogurt produced using Lactiplantibacillus plantarum TOKAI 17 showed the highest inhibition rates in the α-glucosidase and DPP-Ⅳ inhibition assays, respectively. Soymilk yogurt produced using Streptococcus macedonicus TOKAI 4 showed the highest inhibitory activities in Nω-(carboxymethyl) arginine (CMA) and Nε-(carboxymethyl) lysine (CML) formation, respectively. Furthermore, soymilk yogurt prepared using Lb. plantarum TOKAI 17 and Lactiplantibacillus pentosus TOKAI 35 exhibited higher proportions of aglycone isoflavones than soymilk and showed a higher fluorescent AGEs inhibitory activity than that of soymilk (p < 0.05). Interestingly, the inhibition assay assessing fluorescent AGEs formation using isoflavones indicated that aglycone-type isoflavones, such as genistein and daidzein, had higher inhibitory activities than that of glycosides (p < 0.05). These results indicate that soymilk yogurt produced using Lb. plantarum TOKAI 17 and Lb. pentosus TOKAI 35 had inhibitory effects on α-glucosidase, DPP-Ⅳ, and AGEs formation in vitro, and that aglycone isoflavones might inhibit the formation of fluorescent AGEs.
基金This work was supported by JSPS KAKENHI,Japan[No.JP16H05255,JP19H03884(MM),JP17H04654(NM)]scholarship support from the Japanese Government(MEXT)provided to the author(NS).
文摘Alterations in cellular metabolism may contribute to tumor proliferation and survival.Upregulation of the facilitative glucose transporter(GLUT)plays a key role in promoting cancer.GLUT5 mediates modulation of fructose utilization,and its overexpression has been associated with poor prognosis in several cancers.However,its metabolic regulation remains poorly understood.Here,we demonstrated elevated GLUT5 expression in human cholangiocarcinoma(CCA),using RNA sequencing data from samples of human tissues and cell lines,as compared to normal liver tissues or a cholangiocyte cell line.Cells exhibiting highexpression of GLUT5 showed increased rates of cell proliferation and ATP production,particularly in a fructose-supplemented medium.In contrast,GLUT5 silencing attenuated cell proliferation,ATP production,cell migration/invasion,and improved epithelialemesenchymal transition(EMT)balance.Correspondingly,fructose consumption increased tumor growth in a nude mouse xenograft model,and GLUT5 silencing suppressed growth,supporting the tumor-inhibitory effect of GLUT5 downregulation.Furthermore,in the metabolic pathways of fructolysis-Warburg effect,the expression levels of relative downstream genes,including ketohexokinase(KHK),aldolase B(ALDOB),lactate dehydrogenase A(LDHA),and monocarboxylate transporter 4(MCT4),as well as hypoxia-inducible factor 1 alpha(HIF1A),were altered in a GLUT5 expression-dependent manner.Taken together,these findings indicate that GLUT5 could be a potential target for CCA therapeutic approach via metabolic regulation.
