bims-glecem 2022-07-03 papers

bims-glecem

Biomed News

on Glycogen metabolism in exercise, cancer and energy metabolism

Issue of 2022‒07‒03
thirteen papers selected by
Dipsikha Biswas, Københavns Universitet

Liver glycogen phosphorylase is upregulated in glioblastoma and provides a metabolic vulnerability to high dose radiation.
Analysis of the expression, function and signaling of glycogen phosphorylase isoforms in hepatocellular carcinoma.
Co-occurrence of Glycogen Storage Disease Type 2 and Congenital Myasthenic Syndrome Type 5 in a Pediatric Patient: A Case Report.
Effects of endurance training on metabolic enzyme activity and transporter protein levels in the skeletal muscles of orchiectomized mice.
Glycogen synthase kinase-3β inhibitor promotes the migration and osteogenic differentiation of rat dental pulp stem cells via the β-catenin/PI3K/Akt signaling pathway.
Inborn Errors of Metabolism: Becoming Ready for Rare.
Photoelectrochemical sandwich immunoassay of brain glycogen phosphorylase based on methyl orange-sensitized TiO2 nanorods.
Mutations in GCK May Lead to MODY2 by Reducing Glycogen Synthesis.
Novel Hybrid Virtual Screening Protocol Based on Pharmacophore and Molecular Docking for Discovery of GSK-3β Inhibitors.
Site-directed mutagenesis of Serine-72 reveals the location of the fructose 6-phosphate regulatory site of the Agrobacterium tumefaciens ADP-glucose pyrophosphorylase.
Anionically Functionalized Glycogen Encapsulates Melittin by Multivalent Interaction.
Phosphoproteomics reveals that camel and goat milk improve glucose homeostasis in HDF/STZ-induced diabetic rats through activation of hepatic AMPK and GSK3-GYS axis.
α-Amylase inhibition of a certain dietary polyphenol is predominantly affected by the concentration of α-1, 4-glucosidic bonds in starchy and artificial substrates.

Cell Death Dis. 2022 Jun 28. 13(6): 573

Liver glycogen phosphorylase is upregulated in glioblastoma and provides a metabolic vulnerability to high dose radiation.

Christos E Zois, Anne M Hendriks, Syed Haider, Elisabete Pires, Esther Bridges, Dimitra Kalamida, Dimitrios Voukantsis, B Christoffer Lagerholm, Rudolf S N Fehrmann, Wilfred F A den Dunnen, Andrei I Tarasov, Otto Baba, John Morris, Francesca M Buffa, James S O McCullagh, Mathilde Jalving, Adrian L Harris.

Channelling of glucose via glycogen, known as the glycogen shunt, may play an important role in the metabolism of brain tumours, especially in hypoxic conditions. We aimed to dissect the role of glycogen degradation in glioblastoma (GBM) response to ionising radiation (IR). Knockdown of the glycogen phosphorylase liver isoform (PYGL), but not the brain isoform (PYGB), decreased clonogenic growth and survival of GBM cell lines and sensitised them to IR doses of 10-12 Gy. Two to five days after IR exposure of PYGL knockdown GBM cells, mitotic catastrophy and a giant multinucleated cell morphology with senescence-like phenotype developed. The basal levels of the lysosomal enzyme alpha-acid glucosidase (GAA), essential for autolysosomal glycogen degradation, and the lipidated forms of gamma-aminobutyric acid receptor-associated protein-like (GABARAPL1 and GABARAPL2) increased in shPYGL U87MG cells, suggesting a compensatory mechanism of glycogen degradation. In response to IR, dysregulation of autophagy was shown by accumulation of the p62 and the lipidated form of GABARAPL1 and GABARAPL2 in shPYGL U87MG cells. IR increased the mitochondrial mass and the colocalisation of mitochondria with lysosomes in shPYGL cells, thereby indicating reduced mitophagy. These changes coincided with increased phosphorylation of AMP-activated protein kinase and acetyl-CoA carboxylase 2, slower ATP generation in response to glucose loading and progressive loss of oxidative phosphorylation. The resulting metabolic deficiencies affected the availability of ATP required for mitosis, resulting in the mitotic catastrophy observed in shPYGL cells following IR. PYGL mRNA and protein levels were higher in human GBM than in normal human brain tissues and high PYGL mRNA expression in GBM correlated with poor patient survival. In conclusion, we show a major new role for glycogen metabolism in GBM cancer. Inhibition of glycogen degradation sensitises GBM cells to high-dose IR indicating that PYGL is a potential novel target for the treatment of GBMs.

DOI: https://doi.org/10.1038/s41419-022-05005-2
Oncol Lett. 2022 Aug;24(2): 244

Analysis of the expression, function and signaling of glycogen phosphorylase isoforms in hepatocellular carcinoma.

Lingyu Jiang, Shuyan Liu, Tingzhi Deng, Yang Yang, Yin Zhang.

  Glycogen phosphorylase (GP) is an essential enzyme for glycolysis via the glycogen degradation pathway. It consists of three isoforms: PYGB (brain form), PYGL (liver form) and PYGM (muscle form). Although the abnormal expression of GP is associated with a variety of tumors, its relationship with hepatocellular carcinoma (HCC) and whether it can be used as a prognostic marker of HCC remains unclear. In the present study, the expression levels of PYGB, PYGL and PYGM were analyzed. It was found that the expression levels of PYGB in tumor tissues were higher than those in normal tissues, particularly in HCC. The high expression of PYGB (hazard ratios=1.801; 95% confidence interval: 1.266-2.562) could predict the poor prognosis of HCC patients but not PYGL and PYGM. Inhibition of PYGB with GP inhibitor CP91149 significantly suppressed the HCC cell proliferation in the HCC cell model. In addition, combination treatment with sorafenib, a standard treatment for HCC, showed a great inhibition on tumor growth and angiogenesis. These findings suggested that PYGB may be used as a therapeutic and prognostic indicator for HCC.

Keywords:  PYGB; PYGL; PYGM; glycogen phosphorylase; hepatocellular carcinoma

DOI:  https://doi.org/10.3892/ol.2022.13364
Cureus. 2022 Jun;14(6): e26345

Co-occurrence of Glycogen Storage Disease Type 2 and Congenital Myasthenic Syndrome Type 5 in a Pediatric Patient: A Case Report.

Fawzia Al-Sharif, Mohammed F Alamer, Hussein O Taher, Raneem Y Gazzaz, Asma O AlRuwaithi, Tuleen T Miliany, Mohammed A Alrufaihi, Abdullah F Al Amer.

  Glycogen storage disease type 2 (also known as Pompe disease) is a metabolic disorder characterized by an accumulation of glycogen within lysosomes. Pathophysiologically, this condition is caused by an autosomal recessive deficiency of the lysosomal acid alpha-glucosidase enzyme, resulting in defects in lysosomal metabolism. Glycogen accumulation causes advanced muscle weakness (myopathy) throughout the body, including the heart, skeletal muscles, liver, and the neurological system. Currently, there is no definitive treatment for Pompe disease. However, recent studies have indicated that enzyme replacement therapy (ERT) can be effective. Myasthenia gravis (MG) is an autoimmune illness that affects the postsynaptic acetylcholine receptors and causes fatigue that can be eased by rest. MG is frequently accompanied by a thymoma. Dyspnea and/or bulbar symptoms can indicate an imminent crisis requiring immediate intervention. Here, we present a rare case of a four-year-old female patient who initially presented at the age of one month with the infantile form of Pompe disease and congenital myasthenia syndrome type 5. The patient presented with bradycardia, poor suckling, respiratory distress, and respiratory failure requiring assisted ventilation, subglottic stenosis, and tachypnea. Whole exome sequencing was used for definitive diagnosis. ERT (Myozyme) was administered with good results. We propose that early identification and management of Pompe disease with Myozyme can improve patients' condition and ultimately increase the possibility of survival.

Keywords:  autoimmune; autosomal recessive; congenital myasthenia syndrome type 5; enzyme replacement therapy; glycogen storage disease type 2; infant

DOI:  https://doi.org/10.7759/cureus.26345
J Physiol Sci. 2022 Jun 29. 72(1): 14

Effects of endurance training on metabolic enzyme activity and transporter protein levels in the skeletal muscles of orchiectomized mice.

Kenya Takahashi, Yu Kitaoka, Hideo Hatta.

  This study investigated whether endurance training attenuates orchiectomy (ORX)-induced metabolic alterations. At 7 days of recovery after sham operation or ORX surgery, the mice were randomized to remain sedentary or undergo 5 weeks of treadmill running training (15-20 m/min, 60 min, 5 days/week). ORX decreased glycogen concentration in the gastrocnemius muscle, enhanced phosphofructokinase activity in the plantaris muscle, and decreased lactate dehydrogenase activity in the plantaris and soleus muscles. Mitochondrial enzyme activities and protein content in the plantaris and soleus muscles were also decreased after ORX, but preserved, in part, by endurance training. In the treadmill running test (15 m/min, 60 min) after 4 weeks of training, orchiectomized sedentary mice showed impaired exercise performance, which was restored by endurance training. Thus, endurance training could be a potential therapeutic strategy to prevent the hypoandrogenism-induced decline in muscle mitochondrial content and physical performance.

Keywords:  Enzyme; Exercise; Orchiectomy; Skeletal muscle; Transporter

DOI:  https://doi.org/10.1186/s12576-022-00839-z
J Dent Sci. 2022 Apr;17(2): 802-810

Glycogen synthase kinase-3β inhibitor promotes the migration and osteogenic differentiation of rat dental pulp stem cells via the β-catenin/PI3K/Akt signaling pathway.

Huilan Xie, Yi Lin, Fang Fang.

  Background/purpose: Glycogen synthase kinase-3β (GSK3β) inhibitor enhances bone formation, while dental pulp stem cells (DPSC) are potentially used to repair bone defects. The present study aimed to investigate the effect of AR-A014418 (AR, a specific glycogen synthase kinase-3β inhibitor) on the migration and osteogenic differentiation of rat-derived dental pulp stem cells (rDPSCs), and further explore the underlying mechanism.Materials and methods: rDPSCs were isolated from rats, and then cultured with different concentrations of AR with or without LY294002 (a PI3K inhibitor). Then, cell viability, migration, osteogenic differentiation, and the involvement of PI3K pathway were detected by CCK-8 assay, Transwell assay, Alizarin Red S Staining, Alkaline phosphatase (ALP) assay, Western blot, and RT-PCR, respectively.
Results: Our present study demonstrated that AR of various concentrations (1 μM, 2.5 μM, and 5 μM) not only promoted the rDPSC proliferation and migration, but also increased calcium deposition, the activity of alkaline phosphatase (ALP), and levels of osteogenic markers (RUNX2, OPN, OCN, and OSX) in rDPSCs. It was also found that the administration of AR resulted in an increase in the expression level of p-GSK3β (Ser), β-catenin, p-PI3K, and p-Akt, and a reduction in p-GSK3β (Tyr216). Furthermore, PI3K inhibitor LY294002 abrogated the enhanced cell migration and osteogenic differentiation of rDPSCs induced by AR.
Conclusion: Our results provide evidence that AR significantly promotes migration and osteogenic differentiation of rDPSCs by activating β-catenin/PI3K/Akt signaling pathway.

Keywords:  Dental pulp stem cells; Glycogen synthase kinase-3β inhibitor; Migration; Osteogenic differentiation; PI3K

DOI:  https://doi.org/10.1016/j.jds.2021.09.035
Pediatr Rev. 2022 Jul 01. 43(7): 371-383

Inborn Errors of Metabolism: Becoming Ready for Rare.

Samantha A Schrier Vergano.

Inborn errors of metabolism (IEMs) are a large group of disorders that can present in any age group and must be considered in the differential diagnosis for a variety of signs and symptoms appearing in infants and children. The rarity and complexity of these conditions often make them difficult to recognize, as they may mimic more common conditions. This review article discusses some of the more commonly presenting IEMs that are important for the general pediatrician to understand when evaluating a sick patient. Many of these diseases are also on the newborn screen, which pediatricians often encounter as first-line providers. Disorders that are discussed in detail herein include disorders of amino acid metabolism, including amino acidopathies and organic acidurias; urea cycle disorders; defects in fatty acid β-oxidation; disorders of carbohydrate metabolism, including the glycogen storage diseases and galactosemia; and lysosomal storage diseases.

DOI: https://doi.org/10.1542/pir.2022-005088
Mikrochim Acta. 2022 Jul 01. 189(7): 265

Photoelectrochemical sandwich immunoassay of brain glycogen phosphorylase based on methyl orange-sensitized TiO2 nanorods.

Chenglong Sun, Lu Li, Jialin Liu, Yun Du, Yueyi Peng, Qingji Xie.

  The photoelectrochemical immunoassay of glycogen phosphorylase BB (GPBB) was studied. A methyl orange/TiO2 nanorod heterojunction was constructed on a fluorine-doped tin oxide electrode by hydrothermal synthesis, calcination, and chemical adsorption. A sandwich immune structure consisting of GPBB as the first antibody, GPBB, and a CdS@mesoporous silica-ascorbic acid (AA)-GPBB as secondary antibody composite was constructed on each of the selected well surfaces of a 96-well microplate. By adding mercaptoethylamine to structurally destroy the secondary antibody composite and release the electron donor AA, the amplification of photocurrent, and thus the "off-on" photoelectrochemical biosensing of GPBB were realized. The use of the 96-well microplate provides good reproducibility of the assembled immune structures and eliminates the possible effect of the photogenerated hole-induced protein oxidation on the photocurrent. The relevant electrodes and materials were characterized by electrochemistry, UV-vis diffuse reflectance spectra, Fourier transform infrared spectroscopy, X-ray diffractometer, scanning electron microscopy/energy dispersive spectroscopy, transmission electron microscopy and BET method. Under the optimal conditions, the photocurrent was linear with the logarithm of GPBB concentration from 0.005 to 200 ng mL-1 and with a limit of detection of 1.7 pg mL-1 (S/N = 3). Satisfactory results were obtained in the analysis of real serum samples. A sandwich immune structure consisting of GPBB first antibody, GPBB, and a CdS@mesoporous silica-ascorbic acid (AA)-GPBB secondary antibody composite was constructed on each of the selected well surfaces of a 96-well microplate. By adding mercaptoethylamine to structurally destroy the secondary antibody composite and release the electron donor AA, the amplification of photocurrent, and thus the "off-on" photoelectrochemical biosensing of GPBB were realized.

Keywords:  Controlled release of hole scavenger; Glycogen phosphorylase BB; Methyl orange/TiO2 nanorod heterojunction; Photoelectrochemistry; Sandwich-type immunoassay

DOI:  https://doi.org/10.1007/s00604-022-05367-6
Adv Biol (Weinh). 2022 Jun 30. e2200097

Mutations in GCK May Lead to MODY2 by Reducing Glycogen Synthesis.

Zongyue Li, Kunxia Li, Yan Sun, Xiuyun Jiang, Jia Liu, Jingyi Li, Li Fang, Guimei Li, Qingbo Guan, Chao Xu.

  Dysfunction of glucokinase (GCK) caused by mutations in the GCK gene is the main cause of maturity-onset diabetes of the young type-2 (MODY2, also known as GCK-MODY), which is usually present in adolescence or young adulthood. MODY2 is characterized by mild, stable fasting hyperglycemia that presents at birth, usually 5.4-8.3 mmol L-1 , and rarely develops complications from diabetes. The treatment of MODY2 prefers a manageable diet rather than the use of insulin. Previous studies have identified GCK mutations only by online software prediction or enzyme kinetic analysis and thermolability assays which are complicated to be conducted. In this study, six mutations in the GCK gene, including four novel mutations and two mutations that are previously reported, are identified. All the six locations are highly conserved according to the sequencing alignment. Moreover, missense mutations are strongly predicted to be pathogenic using online programs. Functional studies show that mutations in GCK mutation do not affect insulin secretion but affect glycogen synthesis. These findings demonstrate that GCK mutations decrease glycogen synthesis, which leads to hyperglycemia in MODY2. Meanwhile, this study provides a new perspective and methods for identifying pathogenic mutations in GCK.

Keywords:  glucokinase; glycogen synthesis; maturity-onset diabetes of the young type 2

DOI:  https://doi.org/10.1002/adbi.202200097
Chem Biol Drug Des. 2022 Jun 28.

Novel Hybrid Virtual Screening Protocol Based on Pharmacophore and Molecular Docking for Discovery of GSK-3β Inhibitors.

Xiaochang Liu, Jiaxue Yu, Yongyan Luo, Haojian Dong.

  GSK-3β is a member of the GSKs subfamily and plays a major role in the regulation of transcriptional elongation, which has attracted widespread attention as a therapeutic target for AD. In this study, by combining pharmacophore-based virtual screening and kinase inhibition assays, we have successfully identified 4 small molecules that inhibit GSK-3β activity at micromolar potency. These hit compounds showed drug-like properties according to Lipinski's rule of five and ADMET. An inter-complex interaction study showed that all hit compounds adapted well to the ATP pocket of the GSK-3β protein. Among them, hits 2 and 4 displayed considerable inhibitory activities with IC50 value of 0.74 ± 0.04 μM and 2.32 ± 0.84 μM respectively. Overall, the discovered GSK-3β inhibitors act as new chemical leads to develop improved inhibitors that block the interaction of GSK-3β, and the hybrid virtual screening strategy designed in this study provides an important reference for design and synthesis novel selective GSK-3β inhibitors.

Keywords:  GSK-3β; hits 2 and 4; kinase inhibition; pharmacophore-based virtual screening

DOI:  https://doi.org/10.1111/cbdd.14111
Protein Sci. 2022 Jul;31(7): e4376

Site-directed mutagenesis of Serine-72 reveals the location of the fructose 6-phosphate regulatory site of the Agrobacterium tumefaciens ADP-glucose pyrophosphorylase.

Mashael A Alghamdi, Rania A Hussien, Yuanzhang Zheng, Hiral P Patel, Matías D Asencion Diez, Alberto A Iglesias, Dali Liu, Miguel A Ballicora.

  The allosteric regulation of ADP-glucose pyrophosphorylase is critical for the biosynthesis of glycogen in bacteria and starch in plants. The enzyme from Agrobacterium tumefaciens is activated by fructose 6-phosphate (Fru6P) and pyruvate (Pyr). The Pyr site has been recently found, but the site where Fru6P binds has remained unknown. We hypothesize that a sulfate ion previously found in the crystal structure reveals a part of the regulatory site mimicking the presence of the phosphoryl moiety of the activator Fru6P. Ser72 interacts with this sulfate ion and, if the hypothesis is correct, Ser72 would affect the interaction with Fru6P and activation of the enzyme. Here, we report structural, binding, and kinetic analysis of Ser72 mutants of the A. tumefaciens ADP-glucose pyrophosphorylase. By X-ray crystallography, we found that when Ser72 was replaced by Asp or Glu side chain carboxylates protruded into the sulfate-binding pocket. They would present a strong steric and electrostatic hindrance to the phosphoryl moiety of Fru6P, while being remote from the Pyr site. In agreement, we found that Fru6P could not activate or bind to S72E or S72D mutants, whereas Pyr was still an effective activator. These mutants also blocked the binding of the inhibitor AMP. This could potentially have biotechnological importance in obtaining enzyme forms insensitive to inhibition. Other mutations in this position (Ala, Cys, and Trp) confirmed the importance of Ser72 in regulation. We propose that the ADP-glucose pyrophosphorylase from A. tumefaciens have two distinct sites for Fru6P and Pyr working in tandem to regulate glycogen biosynthesis.

Keywords:  ADP-glucose pyrophosphorylase; allosteric regulation; enzyme engineering; glycogen biosynthesis

DOI:  https://doi.org/10.1002/pro.4376
Biomacromolecules. 2022 Jun 29.

Anionically Functionalized Glycogen Encapsulates Melittin by Multivalent Interaction.

Hanna Zhukouskaya, Pablo M Blanco, Zulfiya Černochová, Lucie Čtveráčková, Roman Staňo, Ewa Pavlova, Miroslav Vetrík, Peter Černoch, Marcela Filipová, Miroslav Šlouf, Miroslav Štěpánek, Martin Hrubý, Peter Košovan, Jiří Pánek.

We developed acid-functionalized glycogen conjugates as supramolecular carriers for efficient encapsulation and inhibition of a model cationic peptide melittin─the main component of honeybee venom. For this purpose, we synthesized and characterized a set of glycogens, functionalized to various degrees by several different acid groups. These conjugates encapsulate melittin up to a certain threshold amount, beyond which they precipitate. Computer simulations showed that sufficiently functionalized conjugates electrostatically attract melittin, resulting in its efficient encapsulation in a broad pH range around the physiological pH. Hemolytic assays confirmed in vitro that the effective inhibition of melittin's hemolytic activity occurs for highly functionalized samples, whereas no inhibition is observed when using low-functionalized conjugates. It can be concluded that functional glycogens are promising carriers for cationic molecular cargos or antidotes against animal venoms under conditions, in which suitable properties such as biodegradability and biocompatibility are crucial.

DOI: https://doi.org/10.1021/acs.biomac.2c00400
Food Res Int. 2022 Jul;pii: S0963-9969(22)00311-8. [Epub ahead of print]157 111254

Phosphoproteomics reveals that camel and goat milk improve glucose homeostasis in HDF/STZ-induced diabetic rats through activation of hepatic AMPK and GSK3-GYS axis.

Binsong Han, Lina Zhang, Yanmei Hou, Jinjing Zhong, Kasper Hettinga, Peng Zhou.

  Diabetes is a serious public health problem with global implications. Among many diabetes management therapies, non-pharmacological therapies such as those that focus on diet and exercise are gradually becoming more acceptable to patients. Within dietary management options, dairy products such as camel and goat milk are valued for their specific health benefits. The aim of this study was therefore to investigate the effect of camel and goat milk consumption on glucose homeostasis in high-fat diet and streptozotocin (HFD/STZ) induced diabetic rats. HFD/STZ-induced diabetic rats were fed with different milk for 35 days. Parameters related to glucose homeostasis, as well as hepatic proteome and phosphoproteome were investigated. The results of which showed that camel and goat milk consumption improved fasting glucose levels, glucose tolerance, and indicators related to lipid metabolism, while bovine and sheep milk consumption did not work. In addition, the hepatic phosphoproteome suggests that the ameliorative effect of both camel and goat milk was associated with the activation of AMPK. However, camel milk consumption further elevated the phosphorylation level of hepatic ACC, while goat milk consumption activated GSK3-GYS axis-related proteins. The present study investigated the possible mechanisms by which camel and goat milk consumption improves glucose homeostasis in HFD/STZ-induced diabetic rats and revealed their differences in the mechanism of antidiabetic effect.

Keywords:  AMPK; Camel milk; Diabetes; GSK3-GYS; Goat milk; Phosphoproteome

DOI:  https://doi.org/10.1016/j.foodres.2022.111254
Food Res Int. 2022 Jul;pii: S0963-9969(22)00267-8. [Epub ahead of print]157 111210

α-Amylase inhibition of a certain dietary polyphenol is predominantly affected by the concentration of α-1, 4-glucosidic bonds in starchy and artificial substrates.

Jifan Zhang, Caixia Li, Guidan Wang, Junwei Cao, Xi Yang, Xuebo Liu, Lijun Sun.

  To elucidate why the inhibitory activity of one same polyphenol against α-amylase varies in different works. Seven starchy and three artificial substrates, and a polyphenolic competitive inhibitor, tannic acid (TA) were applied to study the enzyme inhibition in different digestion systems. The results showed that the IC50 values of TA were similar for all starches at the same starch concentration, although there existed difference in starch physiochemical properties, like branching degree, amylose chain distribution, viscosity, and digestion rate. However, the IC50 values significantly decreased with the substrate concentration decreasing, regardless of substrate types. Notably, TA had a similar competitive inhibition constant (Kic) for all the starches, despite the difference in substrate concentration, indicating that the fixed constant unconditionally describes the inhibitor-enzyme binding property. In the TA/amylase/starch system, the physical adsorption of TA with starch was much weaker than the specific binding of TA with α-amylase that was driven by hydrogen bondings and π-stackings. Therefore, it was the substrate, i.e., α-1,4-glucosidic bond concentration, rather than the existing matrix of the bonds, that predominantly affected the inhibitory activity of a polyphenol, because of the competitive action between α-1,4-glucosidic bond and the polyphenol regarding binding with the enzyme.

Keywords:  Binding interactions; Polyphenols; Substrate digestion; α-1,4-glucosidic bonds; α-Amylase Inhibition

DOI:  https://doi.org/10.1016/j.foodres.2022.111210