摘要
OBJECTIVES@#Endothelium-dependent vasodilation dysfunction is the pathological basis of diabetic macroangiopathy. The utilization and adaptation of endothelial cells to high glucose determine the functional status of endothelial cells. Glycolysis pathway is the major energy source for endothelial cells. Abnormal glycolysis plays an important role in endothelium-dependent vasodilation dysfunction induced by high glucose. Pyruvate kinase isozyme type M2 (PKM2) is one of key enzymes in glycolysis pathway, phosphorylation of PKM2 can reduce the activity of pyruvate kinase and affect the glycolysis process of glucose. TEPP-46 can stabilize PKM2 in its tetramer form, reducing its dimer formation and phosphorylation. Using TEPP-46 as a tool drug to inhibit PKM2 phosphorylation, this study aims to explore the impact and potential mechanism of phosphorylated PKM2 (p-PKM2) on endothelial dependent vasodilation function in high glucose, and to provide a theoretical basis for finding new intervention targets for diabetic macroangiopathy.@*METHODS@#The mice were divided into 3 groups: a wild-type (WT) group (a control group, C57BL/6 mice) and a db/db group (a diabetic group, db/db mice), which were treated with the sodium carboxymethyl cellulose solution (solvent) by gavage once a day, and a TEPP-46 group (a treatment group, db/db mice+TEPP-46), which was gavaged with TEPP-46 (30 mg/kg) and sodium carboxymethyl cellulose solution once a day. After 12 weeks of treatment, the levels of p-PKM2 and PKM2 protein in thoracic aortas, plasma nitric oxide (NO) level and endothelium-dependent vasodilation function of thoracic aortas were detected. High glucose (30 mmol/L) with or without TEPP-46 (10 μmol/L), mannitol incubating human umbilical vein endothelial cells (HUVECs) for 72 hours, respectively. The level of NO in supernatant, the content of NO in cells, and the levels of p-PKM2 and PKM2 protein were detected. Finally, the effect of TEPP-46 on endothelial nitric oxide synthase (eNOS) phosphorylation was detected at the cellular and animal levels.@*RESULTS@#Compared with the control group, the levels of p-PKM2 in thoracic aortas of the diabetic group increased (P<0.05). The responsiveness of thoracic aortas in the diabetic group to acetylcholine (ACh) was 47% lower than that in the control group (P<0.05), and that in TEPP-46 treatment group was 28% higher than that in the diabetic group (P<0.05), while there was no statistically significant difference in the responsiveness of thoracic aortas to sodium nitroprusside (SNP). Compared with the control group, the plasma NO level of mice decreased in the diabetic group, while compared with the diabetic group, the phosphorylation of PKM2 in thoracic aortas decreased and the plasma NO level increased in the TEPP-46 group (both P<0.05). High glucose instead of mannitol induced the increase of PKM2 phosphorylation in HUVECs and reduced the level of NO in supernatant (both P<0.05). HUVECs incubated with TEPP-46 and high glucose reversed the reduction of NO production and secretion induced by high glucose while inhibiting PKM2 phosphorylation (both P<0.05). At the cellular and animal levels, TEPP-46 reversed the decrease of eNOS (ser1177) phosphorylation induced by high glucose (both P<0.05).@*CONCLUSIONS@#p-PKM2 may be involved in the process of endothelium-dependent vasodilation dysfunction in Type 2 diabetes by inhibiting p-eNOS (ser1177)/NO pathway.
Subject(s)
Animals , Humans , Mice , Carboxymethylcellulose Sodium/pharmacology , Diabetes Mellitus, Type 2/metabolism , Endothelium, Vascular/metabolism , Glucose/metabolism , Human Umbilical Vein Endothelial Cells , Mice, Inbred C57BL , Nitric Oxide/metabolism , Nitric Oxide Synthase Type III/metabolism , Phosphorylation , Pyruvate Kinase/metabolism , Vasodilation摘要
Primary hepatocellular carcinoma is one of the most common high-grade malignant tumors in the world. Its incidence ranks fifth among malignant tumors in China, and various therapeutic measures have poor curative effect. Pyruvate kinase type M2 is a key enzyme in the glycolytic pathway, and its abnormal expression in liver cancer is closely related to the proliferation, metastasis, diagnosis, treatment, prognosis, as well as drug and radiation resistance. Therefore, multi-pathway targeted regulation of pyruvate kinase type M2 use is expected to become a new direction for the treatment of primary liver cancer.
Subject(s)
Humans , Carcinoma, Hepatocellular , China , Liver Neoplasms , Prognosis , Pyruvate Kinase摘要
OBJECTIVE@#To investigate the effect of glycolytic enzyme pyruvate kinase type 2 (PKM2) on the proliferation and apoptosis of human leukemia HL-60 cells.@*METHODS@#si-PKM2 plasmid was transfected into HL-60 cells (set as si-PKM2 group), and blank vector transfected cells were set as control group (si-Ctl group). The expression levels of PKM2 mRNA and protein in si-Ctl group and si-PKM2 group were detected by RT-qPCR and Western blot. CCK-8 cell detection kit was used to detect the proliferation ability of the cells in the two groups. Flow cytometry was used to detect the changes of cell cycle and apoptosis. Western blot and RT-qPCR were used to detect the changes of p-Akt and p-mTOR protein levels in PI3K/Akt/mTOR signaling pathway and the changes of glycolysis-related mRNA levels of the cells in the two groups. The changes in glucose consumption and lactic acid production of the cells were assayed. Over expressed PKM2, HL-60 cells were treated with PI3K inhibitor LY294002 or galactose, the changes in cell proliferation ability, cell cycle and apoptosis, as well as changes in glucose consumption and lactic acid production were detected.@*RESULTS@#Interfered by si-PKM2, mRNA and protein levels of PKM2 in si-PKM2 group significantly decreased, and proliferation ability of the cells was also reduced (P<0.05). After PKM2 knockdown, the cells were significantly blocked at G@*CONCLUSION@#PKM2 knockdown can inhibit the proliferation and induce apoptosis of HL-60 cells, and its molecular mechanism may be related to the PKM2-mediated PI3K/Akt/mTOR-glycolysis, which suggesting that PKM2 may serve as a molecular target for the prevention and treatment of leukemia.
Subject(s)
Humans , Apoptosis , Cell Proliferation , Glycolysis , Phosphatidylinositol 3-Kinases/metabolism , Pyruvate Kinase摘要
Type 1 diabetes (T1D) is an autoimmune disease characterized by the selective destruction of pancreatic beta cells. In addition to genetic factors, enteroviruses have been considered the main environmental factor involved in this pathology. Therefore, the objective of this study was to evaluate the effects of streptozotocin-induced diabetes and bovine enterovirus (BEV) on liver and kidney pyruvate kinase activity in rats. Fourteen male Wistar rats were divided in three groups: control, diabetes and a third group, which was fed with water experimentally contaminated by BEV. Increased blood glucose levels were found in both diabetes and enterovirus groups, whereas there were no alterations in the lipid profile. A reduced pyruvate kinase activity was observed in the liver and kidney of animals from diabetes and enterovirus groups. Under our experimental conditions, the ingestion of water experimentally contaminated by BEV induced alterations in glycaemia, and also interfered in the pyruvate kinase activity in liver and kidney of the rats, which might be one of the possible mechanisms involved in the T1D development.
Subject(s)
Animals , Cattle , Diabetes Mellitus, Type 1 , Enterovirus, Bovine , Pyruvate Kinase/analysis摘要
BACKGROUND: Fluoranthene (FR) is a common environmental pollutant that exists in a complex mixture with other polycyclic aromatic hydrocarbons (PAHs). We identified biomarkers for monitoring FR exposure and investigated the rescue effect of FR-induced cellular toxicity via aryl hydrocarbon receptor (AHR) antagonist activity in bone marrow derived mesenchymal stem cells (BM-MSCs).METHODS: Morphological changes, viability, and rescue effects of an AHR antagonist (CH223191) were examined in BM-MSCs after exposure to FR. Cytotoxic effects were assayed using the tetrazolium-based colorimetric assay. Apoptosis was measured by annexin V and propidium iodide dye-based flowcytometry assay, mitochondrial membrane potential assay, and nuclear DNA fragmentation assay. Molecular signaling pathways of apoptosis and autophagy were investigated using immunoblotting. Proteomics were performed in order to reveal the spectra of cellular damage and identify biomarkers for FR exposure.RESULTS: Exposing BM-MSCs to FR (IC₅₀=50 µM) induced cell death and morphological changes, while the AHR antagonist showed rescue effects. Autophagy was activated and mitochondrial membrane potential was decreased. Proteomic analysis identified 48 deregulated proteins (26 upregulated and 22 downregulated). Among them, annexin A6, pyruvate kinase, UDP-glucose dehydrogenase, and phospholipase A2 could be potential biomarkers for FR exposure.CONCLUSION: The exposure of BM-MSCs to FR induced remarkable alterations in cellular biology and the proteome, allowing for identification of novel biomarkers for FR exposure. Furthermore, AHR antagonists might be able to prevent cellular damage due to FR exposure.
Subject(s)
Annexin A5 , Annexin A6 , Apoptosis , Autophagy , Biomarkers , Bone Marrow , Cell Death , DNA Fragmentation , Immunoblotting , Membrane Potential, Mitochondrial , Mesenchymal Stem Cells , Oxidoreductases , Phospholipases A2 , Polycyclic Aromatic Hydrocarbons , Propidium , Proteome , Proteomics , Pyruvate Kinase , Receptors, Aryl Hydrocarbon摘要
Abstract Background: Pyruvate kinase deficiency is a hereditary disease that affects the glycolytic pathway of the red blood cell, causing nonspherocytic hemolytic anemia. The disease is transmitted as an autosomal recessive trait and shows a marked variability in clinical expression. This study reports on the molecular characterization of ten Brazilian pyruvate kinase-deficient patients and the genotype-phenotype correlations. Method: Sanger sequencing and in silico analysis were carried out to identify and characterize the genetic mutations. A non-affected group of Brazilian individuals were also screened for the most commonly reported variants (c.1456C>T and c.1529G>A). Results: Ten different variants were identified in the PKLR gene, of which three are reported here for the first time: p.Leu61Gln, p.Ala137Val and p.Ala428Thr. All the three missense variants involve conserved amino acids, providing a rationale for the observed enzyme deficiency. The allelic frequency of c.1456C>T was 0.1% and the 1529G>A variant was not found. Conclusion: This is the first comprehensive report on molecular characterization of pyruvate kinase deficiency from South America. The results allowed us to correlate the severity of the clinical phenotype with the identified variants.
Subject(s)
Humans , Male , Female , Pyruvate Kinase/deficiency , Erythrocytes , Anemia, Hemolytic , Mutation摘要
PURPOSE: The purpose of this study was to observe the effects of metformin on human esophageal cancer cell and to investigate its possible mechanisms. MATERIALS AND METHODS: Cell viability was detected by using a Cell Counting Kit-8, while cell cycle and apoptosis were assessed by flow cytometry and western blot was used to measure the expression of the related proteins. RNAi was used to knockout pyruvate kinase muscle isozyme 2 (PKM2). An Eca109 tumor model was established to evaluate the antitumor effect in vivo. Immunohistochemistry was determined based on the expression of PKM2 and Bim in tumor tissues. Tunnel was used to assess tumor cell apoptosis. RESULTS: Esophageal cancer cells viability was reduced after metformin treatment. The cell cycle was arrested in the G0/G1 phase, apoptosis was induced, caspase 3 was activated, caspase 9 was downregulated, and the pro-apoptotic protein Bim increased. Further study revealed that metformin could suppress the expression of insulin-like growth factor 1 receptor and its downstream proteins, phosphoinositide 3-kinase (PI3K), protein kinase B (AKT/PKB), phosphorylation of AKT (pAKT), mammalian target of rapamycin (mTOR), p70S6K, and PKM2. Insulin-like growth factor 1 partly reversed metfromin-induced apoptosis and attenuated the repression effect of metfomin to PI3K, pAKT, and PKM2. Knockout PKM2 resulted in the activation of caspase 3, down-regulation of caspase 9, and increased expression of Bim. In the Eca109 xenograft model, metformin significantly reduced tumor growth. Furthermore, we found that metformin treatment increased the rate of apoptosis, down-regulation of PKM2, and up-regulation of Bim in tumor tissues. CONCLUSION: Metformin restrained esophageal cancer cell proliferation partly by suppressing the PI3K/AKT/mTOR pathway.
Subject(s)
Humans , Apoptosis , Blotting, Western , Caspase 3 , Caspase 9 , Cell Count , Cell Cycle , Cell Proliferation , Cell Survival , Down-Regulation , Esophageal Neoplasms , Flow Cytometry , Heterografts , Immunohistochemistry , In Vitro Techniques , Metformin , Phosphorylation , Proto-Oncogene Proteins c-akt , Pyruvate Kinase , Repression, Psychology , Ribosomal Protein S6 Kinases, 70-kDa , RNA Interference , Sirolimus , Up-Regulation摘要
PURPOSE: The purpose of this study was to observe the effects of metformin on human esophageal cancer cell and to investigate its possible mechanisms. MATERIALS AND METHODS: Cell viability was detected by using a Cell Counting Kit-8, while cell cycle and apoptosis were assessed by flow cytometry and western blot was used to measure the expression of the related proteins. RNAi was used to knockout pyruvate kinase muscle isozyme 2 (PKM2). An Eca109 tumor model was established to evaluate the antitumor effect in vivo. Immunohistochemistry was determined based on the expression of PKM2 and Bim in tumor tissues. Tunnel was used to assess tumor cell apoptosis. RESULTS: Esophageal cancer cells viability was reduced after metformin treatment. The cell cycle was arrested in the G0/G1 phase, apoptosis was induced, caspase 3 was activated, caspase 9 was downregulated, and the pro-apoptotic protein Bim increased. Further study revealed that metformin could suppress the expression of insulin-like growth factor 1 receptor and its downstream proteins, phosphoinositide 3-kinase (PI3K), protein kinase B (AKT/PKB), phosphorylation of AKT (pAKT), mammalian target of rapamycin (mTOR), p70S6K, and PKM2. Insulin-like growth factor 1 partly reversed metfromin-induced apoptosis and attenuated the repression effect of metfomin to PI3K, pAKT, and PKM2. Knockout PKM2 resulted in the activation of caspase 3, down-regulation of caspase 9, and increased expression of Bim. In the Eca109 xenograft model, metformin significantly reduced tumor growth. Furthermore, we found that metformin treatment increased the rate of apoptosis, down-regulation of PKM2, and up-regulation of Bim in tumor tissues. CONCLUSION: Metformin restrained esophageal cancer cell proliferation partly by suppressing the PI3K/AKT/mTOR pathway.
Subject(s)
Humans , Apoptosis , Blotting, Western , Caspase 3 , Caspase 9 , Cell Count , Cell Cycle , Cell Proliferation , Cell Survival , Down-Regulation , Esophageal Neoplasms , Flow Cytometry , Heterografts , Immunohistochemistry , In Vitro Techniques , Metformin , Phosphorylation , Proto-Oncogene Proteins c-akt , Pyruvate Kinase , Repression, Psychology , Ribosomal Protein S6 Kinases, 70-kDa , RNA Interference , Sirolimus , Up-Regulation摘要
<p><b>OBJECTIVE</b>To evaluate the feasibility of genetic and prenatal diagnosis for a family affected with pyruvate kinase deficiency (PKD).</p><p><b>METHODS</b>Targeted sequence capture and high-throughput sequencing technology was used to detect the exons and exon-intron boundaries of the PKLR gene in a clinically suspected PKD patient. Meanwhile, the genotype of the pedigree was validated by Sanger sequencing. Prenatal genetic diagnosis was performed by amniotic fluid sampling after genotype of the mother of the proband was determined.</p><p><b>RESULTS</b>The proband was found to harbor double heterozygous mutations, c.661G>A (Asp221Asn) and c.1528C>T (Arg510Ter), which resulted in amino acid substitution Asp221Asn and Arg510Ter. Such mutations were confirmed by Sanger sequencing. The mother and father of the proband were detected to have respectively carried c.1528C>T (Arg510Ter) and c.661G>A (Asp221Asn) mutation. The fetus was found to have carried the same mutations as the proband. Following selected abortion, analysis of fetal tissue was consistent with the result of prenatal diagnosis.</p><p><b>CONCLUSION</b>The compound mutations of c.661G>A and c.1528C>T of PKLR gene probably underlie the PKD in the family. Prenatal diagnosis of the mutations analysis can facilitate detection of affected fetus in time.</p>
Subject(s)
Adult , Child, Preschool , Female , Humans , Male , Pregnancy , Anemia, Hemolytic, Congenital Nonspherocytic , Embryology , Genetics , Base Sequence , DNA Mutational Analysis , Exons , Genotype , Molecular Sequence Data , Mutation , Pedigree , Prenatal Diagnosis , Pyruvate Kinase , Genetics , Metabolism , Pyruvate Metabolism, Inborn Errors , Embryology , Genetics摘要
PURPOSE: The aim of our study was to explore the relationships between the M2 isoform of pyruvate kinase (PKM2) and the sensitivity of human non-small cell lung cancer (NSCLC) cells to docetaxel in vitro. MATERIALS AND METHODS: With the method of plasmid transfection, we silenced the expression of PKM2 successfully in A549 and H460 cells. Western blotting and real-time PCR were applied to detect PKM2 expression at protein and gene levels. Cell viability was examined by CCK8 assay. Cell cycle distribution and apoptosis were examined by flow cytometry. P21 and Bax were detected. RESULTS: Expression of PKM2 mRNA and protein were significantly decreased by shRNA targeting PKM2. Silencing of PKM2 increased docetaxel sensitivity of human NSCLC A549 and H460 cells in a collaborative manner, resulting in strong suppression of cell viability. The results of flow cytometric assays suggested that knockdown of PKM2 or docetaxel treatment, whether used singly or in combination, blocked the cells in the G2/M phase, which is in consistent with the effect of the two on the expression of p21. Cells with PKM2 silencing were more likely to be induced into apoptosis by docetaxel although knockdown of PKM2 alone can't induce apoptosis significantly, which is in consistent with the effect of the two on Bax expression. CONCLUSION: The results suggest that PKM2 knockdown could serve as a chemosensitizer to docetaxel in non-small lung cancer cells through targeting PKM2, leading to inhibition of cell viability, increase of cell arrest of G2/M phase and apoptosis.
Subject(s)
Humans , Apoptosis , Blotting, Western , Carcinoma, Non-Small-Cell Lung , Cell Cycle , Cell Line , Cell Survival , Drug Therapy , Flow Cytometry , In Vitro Techniques , Lung Neoplasms , Methods , Plasmids , Pyruvate Kinase , Pyruvic Acid , Real-Time Polymerase Chain Reaction , RNA, Messenger , RNA, Small Interfering , Transfection摘要
After renal injury, selective damage occurs in the proximal tubules as a result of inhibition of glycolysis. The molecular mechanism of damage is not known. Poly(ADP-ribose) polymerase (PARP) activation plays a critical role of proximal tubular cell death in several renal disorders. Here, we studied the role of PARP on glycolytic flux in pig kidney proximal tubule epithelial LLC-PK1 cells using XFp extracellular flux analysis. Poly(ADP-ribosyl)ation by PARP activation was increased approximately 2-fold by incubation of the cells in 10 mM glucose for 30 minutes, but treatment with the PARP inhibitor 3-aminobenzamide (3-AB) does-dependently prevented the glucose-induced PARP activation (approximately 14.4% decrease in 0.1 mM 3-AB-treated group and 36.7% decrease in 1 mM 3-AB-treated group). Treatment with 1 mM 3-AB significantly enhanced the glucose-mediated increase in the extracellular acidification rate (61.1±4.3 mpH/min vs. 126.8±6.2 mpH/min or approximately 2-fold) compared with treatment with vehicle, indicating that PARP inhibition increases only glycolytic activity during glycolytic flux including basal glycolysis, glycolytic activity, and glycolytic capacity in kidney proximal tubule epithelial cells. Glucose increased the activities of glycolytic enzymes including hexokinase, phosphoglucose isomerase, phosphofructokinase-1, glyceraldehyde-3-phosphate dehydrogenase, enolase, and pyruvate kinase in LLC-PK1 cells. Furthermore, PARP inhibition selectively augmented the activities of hexokinase (approximately 1.4-fold over vehicle group), phosphofructokinase-1 (approximately 1.6-fold over vehicle group), and glyceraldehyde-3-phosphate dehydrogenase (approximately 2.2-fold over vehicle group). In conclusion, these data suggest that PARP activation may regulate glycolytic activity via poly(ADP-ribosyl)ation of hexokinase, phosphofructokinase-1, and glyceraldehyde-3-phosphate dehydrogenase in kidney proximal tubule epithelial cells.
Subject(s)
Animals , Cell Death , Epithelial Cells , Glucose , Glucose-6-Phosphate Isomerase , Glycolysis , Hexokinase , Kidney , LLC-PK1 Cells , Oxidoreductases , Phosphofructokinase-1 , Phosphopyruvate Hydratase , Poly Adenosine Diphosphate Ribose , Poly(ADP-ribose) Polymerases , Pyruvate Kinase , Swine摘要
<p><b>OBJECTIVE</b>To explore the molecular mechanism of erythrocyte pyruvate kinase deficiency (PKD).</p><p><b>METHODS</b>Targeted sequence capture and next-generation sequencing (NGS) were used to detect the regions of exon and exon-intron boundarie of PKLR gene in a clinical suspected PKD patient. The protein function of mutant gene was forecasted by the SIFT and PolyPhen-2 databank, after the mutation of PKLR gene in the patient was detected by the NGS technology, its genotype was confirmed by Sanger sequencing.</p><p><b>RESULTS</b>The patient was found to have peculiar double heterozygous mutations: 661 G>A (Asp221Asn) of exon 5 and 1528 C>T (Arg510Ter) of exon 10, resulting in amino acid substitution Asp221Asn and Arg510Ter, these mutations were also further confirmed by Sanger sequencing. The complex mutations were infrequent and each of them was able to cause diseases.</p><p><b>CONCLUSION</b>The complex mutations of both 661 G>A and 1528 C>T of PKLR gene are the molecular mechanism of PKD. Simultaneous existance of above-mentioned complex mutations in PDK patient was never been previously reported at home and abroad.</p>
Subject(s)
Humans , Anemia, Hemolytic, Congenital Nonspherocytic , Genetics , Exons , Genotype , High-Throughput Nucleotide Sequencing , Introns , Mutation , Pyruvate Kinase , Genetics , Pyruvate Metabolism, Inborn Errors , Genetics摘要
OBJECTIVE: Antidepressants are known to positively influence several factors in patients with depressive disorders, resulting in increased neurogenesis and subsequent relief of depressive disorders. To study the effects of venlafaxine during neural differentiation at the cellular level, we looked at its effect on protein expression and regulation mechanisms during neural differentiation. METHODS: After exposing NCCIT cell-derived EBs to venlafaxine during differentiation (1 day and 7 days), changes in protein expression were analyzed by 2-DE and MALDI-TOF MS analysis. Gene levels of proteins regulated by venlafaxine were analyzed by real-time RT-PCR. RESULTS: Treatment with venlafaxine decreased expression of prolyl 4-hydroxylase (P4HB), ubiquitin-conjugating enzyme E2K (HIP2) and plastin 3 (T-plastin), and up-regulated expression of growth factor beta-3 (TGF-beta3), dihydropyrimidinase-like 3 (DPYSL3), and pyruvate kinase (PKM) after differentiation for 1 and 7 days. In cells exposed to venlafaxine, the mRNA expression patterns of HIP2 and PKM, which function as negative and positive regulators of differentiation and neuronal survival, respectively, were consistent with the observed changes in protein expression. CONCLUSION: Our findings may contribute to improve understanding of molecular mechanism of venlafaxine.
Subject(s)
Humans , Antidepressive Agents , Depression , Depressive Disorder , Neurogenesis , Neurons , Prolyl Hydroxylases , Proteomics , Pyruvate Kinase , RNA, Messenger , Venlafaxine Hydrochloride摘要
BACKGROUND/AIMS: M2 pyruvate kinase (M2-PK) is an enzyme that is produced in undifferentiated and proliferating tissues. This study aims to evaluate the usefulness of the immunochromatographic M2 pyruvate kinase (iM2-PK) for the screening of colorectal cancer (CRC) and premalignant lesions. METHODS: Healthy volunteers and patients with colorectal neoplasia were enrolled in six academic hospitals in the capital province of Korea. The iM2-PK value was compared with the immunochromatographic fecal occult blood test (iFOBT) and fecal tumor M2-PK enzyme-linked immunosorbent assay (ELISA). RESULTS: A total of 323 subjects were enrolled. The sensitivity of iM2-PK for CRC was 92.8%, which was superior to iFOBT (47.5%, p<0.0001). For adenomatous lesions, the sensitivity of iM2-PK was 69.4%, which was also superior to iFOBT (12.1%, p<0.001). Compared with M2-PK ELISA, iM2-PK exhibited significantly enhanced sensitivity for CRC (97.5% vs 80.0%, p=0.0289). The sensitivity of iM2-PK was higher in advanced stages of CRC compared with cancers confined to the mucosa and submucosa (p<0.05). However, lymph node metastasis had no influence on the sensitivity of iM2-PK. CONCLUSIONS: The iM2-PK exhibited increased sensitivity for identifying CRC and adenomatous lesions compared with iFOBT. Given its rapid results and convenience, CRC screening using iM2-PK is promising.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Adenoma/diagnosis , Biomarkers, Tumor/analysis , Clinical Enzyme Tests/instrumentation , Colorectal Neoplasms/diagnosis , Enzyme-Linked Immunosorbent Assay , Feces/enzymology , Healthy Volunteers , Chromatography, Affinity/methods , Occult Blood , Precancerous Conditions/diagnosis , Predictive Value of Tests , Pyruvate Kinase/analysis , Reagent Kits, Diagnostic , Republic of Korea , Sensitivity and Specificity摘要
<p><b>OBJECTIVE</b>To screen potential mutation and explore the underlying mechanism for a consanguineous pedigree featuring pyruvate kinase (PK) deficiency.</p><p><b>METHODS</b>The red blood cell pyruvate kinase activities of all family members were detected. All the exons and intron-exon boundaries of the PKLR gene for the proband were amplified and analyzed by direct sequencing. Restriction endonuclease enzymes were used to identify the presence of mutations of all family members.</p><p><b>RESULTS</b>The pyruvate kinase activities were 5.89 U/g Hb in the proband, 3.45, 6.54, 8.87, 7.89, 9.32 U/g Hb in his younger sister, father, mother, grandmother and elder aunt, respectively. The homozygous missense mutation of T>C transition at position 941 in exon 7 of PKLR gene resulted to a Ile314Thr substitution in the proband, and mutant alleles were identified at the level of RNA transcript by cDNA sequence analysis. His younger sister was also homozygous for Ile314Thr. Heterozygosity for Ile314Thr was confirmed in his grandmother, parents and elder aunt.</p><p><b>CONCLUSION</b>Ile314Thr homozygous missense mutation in exon 7 of PKLR is the molecular mechanism of pyruvate kinase deficiency in this family.</p>
Subject(s)
Child, Preschool , Female , Humans , Male , Anemia, Hemolytic, Congenital Nonspherocytic , Genetics , Pedigree , Point Mutation , Pyruvate Kinase , Genetics , Pyruvate Metabolism, Inborn Errors , Genetics摘要
Among ~20 RBC enzyme deficiencies causing hereditary hemolytic anemia (HRA), deficiencies involving three RBC enzymes such as glucose-6-phosphatase, pyruvate kinase and pyrimidine 5'-nucleodiase were known to be relatively common. The methods that have been used for RBC enzyme analysis are based on the kinetic spectrophotometry. This method, however, usually requires multiple step reactions and manual manipulations which are labor-intensive and time-consuming, and carry a greater risk of error due to their complexity. To solve this problem, we had successfully developed the multiplex enzyme analysis for galactose using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). We are now trying to adopt this method to other RBC enzymes associated with HRA. The devised method will allow simple, rapid, sensitive and reproducible quantification of RBC enzymes and should be helpful for the confirmatory diagnosis of HRA caused by RBC enzyme deficiencies.
Subject(s)
Anemia, Hemolytic, Congenital , Galactose , Glucose-6-Phosphatase , Mass Spectrometry , Pyrimidines , Pyruvate Kinase , Spectrophotometry摘要
Among ~20 RBC enzyme deficiencies causing hereditary hemolytic anemia (HRA), deficiencies involving three RBC enzymes such as glucose-6-phosphatase, pyruvate kinase and pyrimidine 5'-nucleodiase were known to be relatively common. The methods that have been used for RBC enzyme analysis are based on the kinetic spectrophotometry. This method, however, usually requires multiple step reactions and manual manipulations which are labor-intensive and time-consuming, and carry a greater risk of error due to their complexity. To solve this problem, we had successfully developed the multiplex enzyme analysis for galactose using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). We are now trying to adopt this method to other RBC enzymes associated with HRA. The devised method will allow simple, rapid, sensitive and reproducible quantification of RBC enzymes and should be helpful for the confirmatory diagnosis of HRA caused by RBC enzyme deficiencies.
Subject(s)
Anemia, Hemolytic, Congenital , Galactose , Glucose-6-Phosphatase , Mass Spectrometry , Pyrimidines , Pyruvate Kinase , Spectrophotometry摘要
The present study consisted of 50 subjects were classified into three groups; Group [GI] Control group consisted of 10 clinically healthy adult subjects of both sexes free from any liver, kidney or cardiovascular diseases. Group [GII] diabetes mellitus type 1 consisted of 20 patients of both sexes. Group [GIII] diabetes mellitus type 1 with nephropathy consisted of 20 patients of both sexes. All subjects were undergo to the following investigated parameters; Ascorbic acid [vitamin C], Catalase, Total antioxidant capacity, Aldolase and Pyruvate kinase enzyme. vitamins C, catalase, total antioxidant capacity enzymes were highly significant decreased [P < 0. 01] in diabetes mellitus type 1 [GII] and diabetes mellitus type 1 with nephropathy [GIII] when compared to the control group. Adolase activity was highly significant increased [P < 0. 01] in diabetes mellitus type 1 with nephropathy [GIII] when compared to the control group. Pyruvate Kinase activity was highly significant increased [P < 0. 01] in diabetes mellitus type 1 [GII] when compared to the control group. The antioxidant and enzymes can be used for follow up in patients suffering from diabetes mellitus type 1 and predict other complications
Subject(s)
Humans , Male , Female , Ascorbic Acid/blood , Antioxidants/blood , Aldehyde-Lyases/blood , Fructose-Bisphosphate Aldolase/blood , Pyruvate Kinase/blood , Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2摘要
The RBC enzyme deficiencies causing hereditary hemolytic anemia (HHA) can be divided into three groups: those participating in the glycolytic (E-M) pathway; those involved with the maintenance of a high ratio of reduced to oxidized glutathione; one enzyme in the nucleotide degradation and salvage pathway. Although RBC enzyme deficiencies causing HHA are rare, 3 of the 15 kinds of important and relatively frequently reported enzyme deficiencies such as pyruvate kinase, glucose-6-phosphate-dehydrogenase and pyrimidine-5'-nucleotidase deficiencies are briefly reviewed. The molecular genetics, clinical symptoms, diagnosis and therapeutic approaches of each enzyme deficiencies are summerized. As these enzyme deficiencies are reported throughout the world as well as in Korea with the identification of the mutations, considering a broad spectrum of etiologies for the diagnosis of HHA seems to be warranted.