Phosphoglucomutase-1 deficiency: Early presentation, metabolic management and detection in neonatal blood spots.

Phosphoglucomutase 1 deficiency is a congenital disorder of glycosylation (CDG) with multiorgan involvement affecting carbohydrate metabolism, N-glycosylation and energy production. The metabolic management consists of dietary D-galactose supplementation that ameliorates hypoglycemia, hepatic dysfunction, endocrine anomalies and growth delay. Previous studies suggest that D-galactose administration in juvenile patients leads to more significant and long-lasting effects, stressing the urge of neonatal diagnosis (0-6 months of age). Here, we detail the early clinical presentation of PGM1-CDG in eleven infantile patients, and applied the modified Beutler test for screening of PGM1-CDG in neonatal dried blood spots (DBSs). All eleven infants presented episodic hypoglycemia and elevated transaminases, along with cleft palate and growth delay (10/11), muscle involvement (8/11), neurologic involvement (5/11), cardiac defects (2/11). Standard dietary measures for suspected lactose intolerance in four patients prior to diagnosis led to worsening of hypoglycemia, hepatic failure and recurrent diarrhea, which resolved upon D-galactose supplementation. To investigate possible differences in early vs. late clinical presentation, we performed the first systematic literature review for PGM1-CDG, which highlighted respiratory and gastrointestinal symptoms as significantly more diagnosed in neonatal age. The modified Butler-test successfully identified PGM1-CDG in DBSs from seven patients, including for the first time Guthrie cards from newborn screening, confirming the possibility of future inclusion of PGM1-CDG in neonatal screening programs. In conclusion, severe infantile morbidity of PGM1-CDG due to delayed diagnosis could be prevented by raising awareness on its early presentation and by inclusion in newborn screening programs, enabling early treatments and galactose-based metabolic management.

Phosphoglucomutase activity as a novel biomarker in patients with acute myocardial infarction.

BACKGROUND: Phosphoglucomutase (PGM), a key enzyme in cellular glucose utilization and energy homeostasis, has been reported to show a relationship with oxidative stress. However, the clinical importance of PGM activity has not been investigated in patients with ischemic heart disease (IHD). The aim of the present pilot study was to clarify whether PGM activity has potential as a cardiovascular risk predictor in patients with IHD. METHODS AND RESULTS: The levels of serum PGM activity in 237 patients with IHD (63 patients with acute myocardial infarction (AMI) and 174 patients with stable effort angina pectoris (EAP)) were evaluated. PGM activity was compared with levels of various myocardial, thrombosis, and inflammatory biomarkers on admission. PGM activity in the AMI group was significantly increased relative to that in the EAP group on admission (AMI, 55.5 µmol·min(-1)·L(-1) (U/L); EAP, 14.4 U/L (P<0.001)), and was observed to increase in parallel with well-established myocardial markers (P<0.001). Moreover, PGM activity and the lipid, thrombosis, and inflammatory biomarkers in the AMI group were higher than those in the EAP group. CONCLUSIONS: PGM activity increased with levels of myocardial, thrombosis, and inflammatory biomarkers in patients with AMI, and might be useful in diagnostic applications during the acute phase in patients with AMI.

Multiplexed detection of DOCK8, PGM3 and STAT3 proteins for the diagnosis of Hyper-Immunoglobulin E syndrome using gold nanoparticles-based immunosensor array platform.

Multiplexed biosensors hold great promise for early diagnosis of diseases where the detection of multiple biomarkers is required. Hyper Immunoglobulin E syndromes (HIES) are rare primary immunodeficiency disorders associated with mutations either in the signal transducer and activator of transcription 3 (STAT3), dedicator of cytokinesis 8 DOCK8) or phosphoglucomutase 3 (PGM3) genes. Yet, the diagnosis of HIES is challenged by the complexity of the existing laboratory assays. Here, we report for the first time the development of a multiplexed electrochemical immunosensor for the simultaneous detection of DOCK8, STAT3 and PGM3 proteins. The immunosensor was constructed on carbon array electrodes that were first modified by electrodeposition of gold nanoparticles (AuNPs). The array electrodes were then used to immobilize specific antibodies for the three proteins after the functionalization of the electrodes with cysteamine/glutaraldehyde linkers. The simultaneous detection of the DOCK8, PGM3 and STAT3 proteins was successfully realized by the immunosensor with respective limits of detections of 3.1, 2.2 and 3.5 pg/ml. The immunosensor has shown good sensitivity as well as selectivity against other proteins such as cystic fibrosis transmembrane conductance regulator (CFTR) and Duchenne Muscular Dystrophy (DMD). Moreover, the immunosensor was successfully applied in human serum samples showing capability to distinguish the HIES from the control samples.

Heterogeneity of human platelets. V. Differences in glycolytic and related enzymes with possible relation to platelet age.

Human platelets were separated by desity-centrifugation into heavy and light populations. Heavy platelets have an average volume approximately twofold greater than light platelets, and have previously been shown to be young platelets. All 11 enzymes of the Embden-Meyerhof pathway plus the five related enzymes: phosphoglucomutase, glucose-6-P dehydrogenase, 6-P-gluconic dehydrogenase, alpha-glycerol-P dehydrogenase, and glutathione reductase (TPNH) were examined in cell lysates from total, heavy, and light platelet populations. Apparent Km for individual enzymes were measured in a total platelet population. Empirical V(max) of the individual enzymes were measured in total, heavy, and light platelet populations. The three apparent rate-limiting enzymes for glycolysis were hexokinase, phosphofructokinase, and glyceraldehyde-3-P dehydrogenase. Heavy platelets contained approximately twofold greater enzyme activity (per gram wet weight) than light platelets for 7 of the 16 enzymes measured: hexokinase, phosphohexoisomerase, phosphofructokinase, glyceraldehyde-3-P dehydrogenase, phosphoglycerokinase, lactic dehydrogenase, and phosphoglucomutase. Heavy platelets also contained 1.9-fold greater reduced glutathione (GSH), 1.7-fold greater DPNH, and 1.2-fold greater TPNH than light platelets. Heavy platelets contained 1.8-fold less lipid peroxidation products (malonyl aldehyde equivalents) than light platelets and were 2.4-fold more resistant to lipid peroxidation catalyzed by 0.1 mM FeCl(3). Sterile incubation of heavy platelets, in vitro for 17 hr, resulted in a significant loss of enzyme activity for the "elevated" seven enzymes when compared with the remainder. Reducing agents such as GSH (0.1 mM), ascorbic acid (0.1 mM), and dithiothreitol (0.01 mM), when added to the incubation mixture, significantly reduced the in vitro loss of activity. In vitro incubation was also associated with a significant loss of GSH and DPNH and a 1.8-fold increase in lipid peroxidation products.

PGM1 deficiency diagnosed during an endocrine work-up of low IGF-1 mediated growth failure.

OBJECTIVE AND IMPORTANCE: Phosphoglucomutase 1 (PGM1) deficiency, first described as a glycogenosis (type XIV) is also a congenital disorder of glycosylation (CDG). We want to illustrate the wide clinical spectrum of PGM1 deficiency and in particular the associated disturbance in glucose metabolism and the endocrine dysfunction. Treatment with d-galactose is experimental. CASE PRESENTATION: PGM1 deficiency was diagnosed in an 8-year-old boy, who was referred because of an unexplained complex syndrome, including recurrent hypoglycaemia and low IGF-1 mediated growth failure. CONCLUSION: The timely diagnosis of this disorder is particularly important, because d-galactose treatment can improve the latter symptoms.

Human erythrocyte phosphoglucomutase: comparison of the kinetic properties of PGM1 and PGM2 isoenzymes.

Kinetic properties of PGM1 and PGM2 phosphoglucomutase "primary" isoenzymes from human erythrocytes were studied. The two enzyme forms share a "ping-pong" kinetic mechanism and show similar Km for substrate (glucose 1-P) and cofactor (glucose 1,6-P2). Micromolar concentrations of fructose 1,6-P2 and glycerate 2,3-P2 inhibit both PGM1 and PGM2 isoenzymes to a similar extent. The sole PGM2 form is affected by ribose monophosphates (ribose 1-P and ribose 5-P) that act as mutase inhibitors vs. glucose 1,6-P2 and as apparent activators vs. glucose 1-P. The interaction between PGM2 isoenzyme and ribose monophosphates is discussed in the light of the ability of this form to also display phosphoribomutase activity.

Fetal growth, gestation length and phosphoglucomutase-1 phenotype.

This study investigates reports that phosphoglucomutase-1 (PGM1) phenotype is associated with fetal growth and gestation length. A total of 350 women were studied, 234 having uncomplicated pregnancies and 114 with a baby weighing greater than 90th centile, corrected for parity, gestation and fetal sex. All women had gestation confirmed by early ultrasound. Conventional cellulose acetate electrophoresis was used to distinguish the three common PGM1 phenotypes and polyacrylamide gel isoelectric focusing to distinguish the ten PGM1 subtypes. Neither PGM1 phenotype nor subtype were found to be associated with gestation length or standardised birth weight. Logistic regression, where maternal age, parity, fetal sex, maternal weight, gestation and smoking were introduced as explanatory variables in addition to PGM1 phenotype testing against the dependent variables birth weight, standardised birth weight and gestation length, did not show differences related to PGM1 phenotype. Two possible reasons for the discrepancy with previously published data are discussed. We conclude that the study provides no support for the belief that PGM1 phenotype is related to fetal growth or gestation length and that the original observations could have arisen as a result of statistical artefact due to multiple testing.

Phenotyping of eight erythrocytic enzymes in one acrylamide gel.

A procedure has been developed to phenotype eight erythrocytic enzymes, phosphoglucomutase (PGM1), adenylate kinase (AK), 6-phosphogluconate dehydrogenase (6PGD), adenosine deaminase (ADA), glyoxalase (GLO), esterase-D (EsD), acid phosphatase (AcP), and glutamic pyruvate transaminase (GPT) in one acrylamide gel and also to detect the presence of common abnormal hemoglobins. The agar overlay technic has been eliminated. This simplified procedure renders the phenotyping of erythrocytic enzymes practical in paternity testing.

Types of serum proteins and erythrocyte enzymes in rheumatoid patients.

Four group systems of serum proteins (Hp, Gc, Km, Gm) and five group systems of erythrocyte enzymes (AP, PGM1, GPT, AK, EsD) were determined in samples of patients with rheumatoid arthritis and in healthy controls. Statistically significant differences were found in Gm system, namely Gm(1) factor was more frequent in rheumatoid patients than in healthy subjects.

Low blood protein heterozygosity in zoo-bred hamadryas baboons.

An electrophoretic study of erythrocyte allozymes and serum proteins representing 32 genetic loci in 32 hamadryas baboons (Papio H.hamadryas) from Cologne and Frankfurt zoos revealed biallelic polymorphism in phosphoglucomutase (PGM), mannose phosphate isomerase (MPI) and transferrin (Tf). Polymorphism amounted to P = 0.097 over 31 loci and observed heterozygosity to H(o) = 0.011, indicating significant reduction from the respective gene diversity parameters encountered in free-living hamadryas baboons. Polygynous mating reduced numbers of heterozygotes at the Tf and the PGM-II loci significantly below Hardy-Weinberg expectations. This results support the importance of active genetic management in programmes for captive breeding and species conservation.

Red cell phosphoglucomutase (PGM1) subtypes in Egyptians.

The polymorphism of the human red cell phosphoglucomutase 1 (PGM1) in samples from Egyptians (n = 134) was investigated using isoelectric focusing in thin-layer polyacrylamide gel. In the studied population samples nine common phenotypes were observed, and the calculated frequencies for the genes PGM1+1, PGM1-1, PGM2+1 and PGM2-1 were 0.6381, 0.0821, 0.2201 and 0.0597, respectively. The observed and expected phenotypes provide a good fit to Hardy-Weinberg equilibrium. The four alleles system will increase the probability of excluding a man falsely accused of paternity to 30% as compared with 16% if the two alleles system is used.

Red cell PGM1 (phosphoglucomutase) phenotyping by isoelectric focussing and starch gel electrophoresis in cases of disputed paternity in the United Kingdom. An evaluation of the results obtained in 95 cases.

Using two techniques for red cell PGM1 (phosphoglucomutase) phenotyping, namely starch gel electrophoresis and isoelectric focussing, a parallel study has been carried out in 95 paternity cases. The results again confirm the genetic basis for the extended polymorphism revealed by isoelectric focussing. Fifteen men were excluded from paternity on the basis of isoelectric focussing compared with seven excluded by starch gel electrophoresis. This was found to be in good agreement with the predicted increase in exclusion rate that the isoelectric focussing technique for red cell PGM1 provides.

Non-equilibrium pH gradient electrophoresis (NEPHGE) on ultrathin polyacrylamide gels containing separators: improved erythrocyte phosphoglucomutase (PGM) and esterase D (EsD) diagnosis in red cell lysates and bloodstains.

Two rapid and reliable electrophoretic techniques for PGM1 and EsD typing on ultrathin polyacrylamide gels are described. They have been based on non-equilibrium pH gradient electrophoresis and on the addition of chemical spacers (EPPS for PGM1 and HEPES for EsD) to the gel mixture.

Simultaneous identification and determination of species origin, ABH antigens and isoenzyme markers in the same bloodstain.

A reliable procedure for the simultaneous identification of blood, determination of species origin and ABH antigens, and typing of isoenzyme markers from a sample of three 1-cm threads is described. Results obtained from known control as well as from casework bloodstains using this procedure were consistent with those obtained in parallel, conventional, individual tests under blind trial conditions.

Population data on the forensic genetic markers: phosphoglucomutase-1, esterase D, erythrocyte acid phosphatase and glyoxylase I.

Blood specimens from white and black sample populations from Baltimore, Maryland, were analyzed for the four most forensically important, polymorphic red cell enzyme systems-phosphoglucomutase-1, esterase D, erythrocyte acid phosphatase and glyoxalase I. The distributions of the phenotypes for each marker in each racial group were in Hardy-Weinberg equilibrium. The population data were similar to previously reported data for Whites and Blacks from different geographical locations within the United States.

Studies and observations on the use of isoelectric focusing in ultra-thin polyacrylamide gels as a method of typing human red cell phosphoglucomutase.

The technique of isoelectric focusing in ultra-thin polyacrylamide gels as a method of typing human red cell phosphoglucomutase (PGM1) has been studied. Typing was possible without the samples attaining true equilibrium focusing conditions. The isozyme patterns so obtained were clearly defined and free from distortion. The importance of assessing relative band intensities when interpreting the isozyme patterns is discussed. Our experience of using the technique to analyse casework material is described.

Isoelectric points and charge-dependent separation of erythrocyte phosphoglucomutase isoenzymes (PGM1 and PGM2).

Phosphoglucomutase can bind both negative and positive ions so that it may change its net electric charge according to the buffer species of the medium. For this reason the knowledge of the pIs of the erythrocyte phosphoglucomutase isoenzymes is not sufficient to forecast their separability by procedures based on charge separations such as ion exchange chromatography. In this paper we indicate the condition to obtain a satisfactory separation of the main erythrocyte phosphoglucomutase isoenzymes by DEAE-cellulose column chromatography. The pI values of the isolated isoenzymes are also reported and compared to those measured by others on whole hemolysates.

Phosphoglucomutase (PGM) grouping of bloodstains on silver.

This paper describes a case involving alteration of phosphoglucomutase (PGM) isoenzyme patterns in bloodstains present on silver. The effect could be produced by treating blood samples with silver nitrate solution.