The polyol pathway is an evolutionarily conserved system for sensing glucose uptake

SummaryCells must adjust the expression levels of metabolic enzymes in response to fluctuating nutrient supply. For glucose, such metabolic remodeling is highly dependent on a master transcription factor ChREBP/MondoA. However, it remains elusive how glucose fluctuations are sensed by ChREBP/MondoA despite the stability of major glycolytic pathways. Here we show that in both flies and mice, ChREBP/MondoA activation in response to glucose ingestion depends on an evolutionarily conserved glucose-metabolizing pathway: the polyol pathway. The polyol pathway converts glucose to fructose via sorbitol. It has been believed that this pathway is almost silent, and its activation in hyperglycemic conditions has deleterious effects on human health. We show that the polyol pathway is required for the glucose-induced nuclear translocation of Mondo, a Drosophila homologue of ChREBP/MondoA, which directs gene expression for organismal growth and metabolism. Likewise, inhibition of the polyol pathway in mice impairs ChREBP’s nuclear localization and reduces glucose tolerance. We propose that the polyol pathway is an evolutionarily conserved sensing system for the glucose uptake that allows metabolic remodeling.

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Prep1 Deficiency Induces Protection from Diabetes and Increased Insulin Sensitivity through a p160-Mediated Mechanism

Molecular and Cellular Biology ◽

10.1128/mcb.00117-08 ◽

2008 ◽

Vol 28 (18) ◽

pp. 5634-5645 ◽

Cited By ~ 35

Author(s):

Francesco Oriente ◽

Luis Cesar Fernandez Diaz ◽

Claudia Miele ◽

Salvatore Iovino ◽

Silvia Mori ◽

...

Keyword(s):

Skeletal Muscle ◽

Insulin Sensitivity ◽

Glucose Uptake ◽

Normal Glucose Tolerance ◽

Glucose Disposal ◽

Protein Levels ◽

Normal Glucose ◽

Enhanced Expression ◽

The Stability

ABSTRACT We have examined glucose homeostasis in mice hypomorphic for the homeotic transcription factor gene Prep1. Prep1-hypomorphic (Prep1 i / i ) mice exhibit an absolute reduction in circulating insulin levels but normal glucose tolerance. In addition, these mice exhibit protection from streptozotocin-induced diabetes and enhanced insulin sensitivity with improved glucose uptake and insulin-dependent glucose disposal by skeletal muscle. This muscle phenotype does not depend on reduced expression of the known Prep1 transcription partner, Pbx1. Instead, in Prep1 i / i muscle, we find normal Pbx1 but reduced levels of the recently identified novel Prep1 interactor p160. Consistent with this reduction, we find a muscle-selective increase in mRNA and protein levels of PGC-1α, accompanied by enhanced expression of the GLUT4 transporter, responsible for insulin-stimulated glucose uptake in muscle. Indeed, using L6 skeletal muscle cells, we induced the opposite effects by overexpressing Prep1 or p160, but not Pbx1. In vivo skeletal muscle delivery of p160 cDNA in Prep1 i / i mice also reverses the molecular phenotype. Finally, we show that Prep1 controls the stability of the p160 protein. We conclude that Prep1 controls insulin sensitivity through the p160-GLUT4 pathway.

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14-Deoxy-11,12-Didehydroandrographolide Ameliorates Glucose Intolerance Enhancing the LKB1/AMPKα/TBC1D1/GLUT4 Signaling Pathway and Inducing GLUT4 Expression in Myotubes and Skeletal Muscle of Obese Mice

The American Journal of Chinese Medicine ◽

10.1142/s0192415x21500695 ◽

2021 ◽

pp. 1-19

Author(s):

Chih-Chieh Chen ◽

Chong-Kuei Lii ◽

Chia-Wen Lo ◽

Yi-Hsueh Lin ◽

Ya-Chen Yang ◽

...

Keyword(s):

Insulin Resistance ◽

Skeletal Muscle ◽

Glucose Uptake ◽

Signaling Pathway ◽

Nuclear Translocation ◽

Time Dependent ◽

Antidiabetic Activity ◽

C2c12 Myotubes ◽

Dependent Manner ◽

Compound C

14-Deoxy-11,12-didehydroandrographolide (deAND), a bioactive component of Andrographis paniculata, has antidiabetic activity. AMP-activated protein kinase (AMPK) regulates glucose transport and ameliorates insulin resistance. The aim of the present study was to investigate whether activation of AMPK is involved in the mechanism by which deAND ameliorates insulin resistance in muscles. deAND amounts up to 40 [Formula: see text]M dose-dependently activated phosphorylation of AMPK[Formula: see text] and TBC1D1 in C2C12 myotubes. In addition, deAND significantly activated phosphorylation of LKB1 at 6 h after treatment, and this activation was maintained up to 48 h. deAND increased glucose uptake at 18 h after treatment, and this increase was time dependent up to 72 h. Compound C, an inhibitor of AMPK, suppressed deAND-induced phosphorylation of AMPK[Formula: see text] and TBC1D1 and reversed the effect on glucose uptake. In addition, the expression of GLUT4 mRNA and protein in C2C12 myotubes was up-regulated by deAND in a time-dependent manner. Promotion of GLUT4 gene transcription was verified by a pGL3-GLUT4 (837 bp) reporter assay. deAND also increased the nuclear translocation of MEF-2A and PPAR[Formula: see text]. After 16 weeks of feeding, the high-fat diet (HFD) inhibited phosphorylation of AMPK[Formula: see text] and TBC1D1 in skeletal muscle of obese C57BL/6JNarl mice, and deactivation of AMPK[Formula: see text] and TBC1D1 by the HFD was abolished by deAND supplementation. Supplementation with deAND significantly promoted membrane translocation of GLUT4 compared with the HFD group. Supplementation also significantly increased GLUT4 mRNA and protein expression in skeletal muscle compared with the HFD group. The hypoglycemic effects of deAND are likely associated with activation of the LKB1/AMPK[Formula: see text]/TBC1D1/GLUT4 signaling pathway and stimulation of MEF-2A- and PPAR[Formula: see text]-dependent GLUT4 gene expression, which account for the glucose uptake into skeletal muscle and lower blood glucose levels.

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Abstract 280: Increased Metabolite Levels of Glycolysis and Pentose Phosphate Pathway in Rabbit Atherosclerotic Arteries and Hypoxic Macrophage

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.34.suppl_1.280 ◽

2014 ◽

Vol 34 (suppl_1) ◽

Author(s):

Atsushi Yamashita ◽

Yan Zhao ◽

Yunosuke Matsuura ◽

Kazuaki Yamasaki ◽

Sayaka Moriguchi-Goto ◽

...

Keyword(s):

Glucose Uptake ◽

Pentose Phosphate Pathway ◽

Nuclear Translocation ◽

Tricarboxylic Acid Cycle ◽

Pentose Phosphate ◽

Plasminogen Activator Inhibitor 1 ◽

Hexokinase Ii ◽

Femoral Arteries ◽

Metabolic Systems ◽

18F Fdg

Aims: Inflammation and possibly hypoxia largely affect glucose utilization in atherosclerotic arteries, which could alter many metabolic systems. However, metabolic changes in atherosclerotic plaques remain unknown. The present study aims to identify changes in metabolic systems relative to glucose uptake and hypoxia in rabbit atherosclerotic arteries and cultured macrophages. Methods: Macrophage-rich or smooth muscle cell (SMC)-rich neointima was created by balloon injury in the iliac-femoral arteries of rabbits fed with a 0.5% cholesterol diet or a conventional diet. THP-1 macrophages stimulated with lipopolysaccharides (LPS) and interferon-γ (INFγ) were cultured under normoxic and hypoxic conditions. We evaluated comprehensive arterial and macrophage metabolism by performing metabolomic analyses using capillary electrophoresis-time of flight mass spectrometry. We evaluated glucose uptake and its relationship to vascular hypoxia using 18F-fluorodeoxyglucose (18F-FDG) and pimonidazole, a marker of hypoxia. Results: The levels of many metabolites increased in the iliac-femoral arteries with macrophage-rich neointima, compared with those that were not injured and those with SMC-rich neointima (glycolysis, 4 of 9; pentose phosphate pathway, 4 of 6; tricarboxylic acid cycle, 4 of 6; nucleotides, 10 of 20). The uptake of 18F-FDG in arterial walls measured by autoradiography positively correlated with macrophage- and pimonidazole-immunopositive areas (r = 0.76, and r = 0.59 respectively; n = 69 for both; p < 0.0001). Pimonidazole immunoreactivity was closely localized with the nuclear translocation of hypoxia inducible factor-1α and hexokinase II expression in macrophage-rich neointima. The levels of glycolytic (8 of 8) and pentose phosphate pathway (4 of 6) metabolites increased in LPS and INFγ stimulated macrophages under hypoxic but not normoxic condition. Plasminogen activator inhibitor-1 protein levels in the supernatant were closely associated with metabolic pathways in the macrophages. Conclusion: Infiltrative macrophages in atherosclerotic arteries might affect metabolic systems, and hypoxia but not classical activation might augment glycolytic and pentose phosphate pathways in macrophages.

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Abstract 102: Cardiac-specific Overactivation of the Mechanistic Target of Rapamycin Complex 1 Induces Metabolic, Structural and Functional Remodeling

Circulation Research ◽

10.1161/res.117.suppl_1.102 ◽

2015 ◽

Vol 117 (suppl_1) ◽

Author(s):

Giovanni Davogustto ◽

Rebecca Salazar ◽

Hernan Vasquez ◽

Heinrich Taegtmeyer

Keyword(s):

Glucose Uptake ◽

Glucose Transporter ◽

Target Of Rapamycin ◽

Glycolytic Intermediate ◽

Glucose Transporter 1 ◽

Structural Remodeling ◽

Mechanistic Target Of Rapamycin ◽

Metabolic Remodeling ◽

Functional Remodeling ◽

Mtorc1 Activation

The heart remodels metabolically and structurally before it fails. Metabolically, the heart increases its reliance on carbohydrates for energy provision. Structurally, the heart hypertrophies to sustain increased hemodynamic stress. There is evidence suggesting that the activation of the mechanistic Target Of Rapamycin Complex 1 (mTORC1) pathway is closely tied to glucose uptake by the heart to drive the metabolic and structural remodeling. We have previously shown that with insulin stimulation or increases in workload, the glycolytic intermediate glucose 6-phosphate (G6P) is required to activate mTORC1. Sustained mTORC1 activation leads, in turn, to ER stress and contractile dysfunction. Studies by others in the kidney have shown that mTORC1 activation upregulates glucose transporter 1 (Glut1) expression and glucose uptake. We therefore test the hypothesis that chronic mTORC1 overactivation results in G6P accumulation, and precedes structural and functional remodeling in the heart. We developed mice with inducible, cardiac-specific deficiency of the protein tuberin (TSC2), a member of the tuberous sclerosis complex, the principal inhibitor of mTORC1. Intracellular G6P concentrations were measured enzymatically. Immunoblotting was performed on protein markers to confirm activation of mTORC1 downstream targets and of the unfolded protein response. Histologic analysis were performed to assess structural changes. Serial echocardiograms were performed to evaluate cardiac function. The results indicate that chronic mTORC1 activation through inducible, cardiac-specific deletion of TSC2 is accompanied by G6P accumulation and metabolic remodeling. Metabolic remodeling precedes structural and functional remodeling. We suggest that in the heart, sustained mTORC1 activation is a key driver of metabolic and structural remodeling.

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Hemodynamics and metabolism of the in vivo vascularly isolated canine pancreas.

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1979.236.6.e626 ◽

1979 ◽

Vol 236 (6) ◽

pp. E626

Author(s):

R J Alteveer ◽

M J Jaffe ◽

J Van Dam

Keyword(s):

Blood Flow ◽

Glucose Uptake ◽

Venous Blood ◽

Fatty Acid Uptake ◽

Acid Uptake ◽

Anesthetized Dogs ◽

Metabolic Variables ◽

The Stability ◽

First Time

Surgical procedures are detailed that have yielded for the first time an in vivo vascularly isolated, autoperfused preparation of the entire pancreas in anesthetized dogs. Previous studies had isolated only part of the pancreas or had resorted to blood-flow techniques not requiring pooled pancreatic venous blood, necessary for metabolic studies of the organ. Pancreatic blood flow (48 ml/min), O2 uptake (180 mumol/min), glucose uptake (51.0 mumol/min), lactate output (6.6 mumol/min), net free fatty acid uptake (2.23 mumol/min), all per 100 g tissue, and various other measured and calculated hemodynamic and metabolic variables were determined on the preparation during control conditions. The stability of the preparation was verified by serial determinations of these parameters and of blood alpha-amylase and beta-glucuronidase levels from 1 to 2.5 h postsurgery. Metabolic rate and glucose uptake were both found to be much higher than in intestinal tissues and approached values characteristic of liver tissue.

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HP1γ Sensitizes Cervical Cancer Cells to Cisplatin through the Suppression of UBE2L3

International Journal of Molecular Sciences ◽

10.3390/ijms21175976 ◽

2020 ◽

Vol 21 (17) ◽

pp. 5976 ◽

Cited By ~ 1

Author(s):

Sang Ah Yi ◽

Go Woon Kim ◽

Jung Yoo ◽

Jeung-Whan Han ◽

So Hee Kwon

Keyword(s):

Cervical Cancer ◽

Cancer Cells ◽

Nuclear Export ◽

Nuclear Translocation ◽

Leptomycin B ◽

P53 Signaling ◽

Cervical Cancer Cells ◽

Ubiquitin Conjugating Enzyme ◽

The Stability

Cisplatin is the most frequently used agent for chemotherapy against cervical cancer. However, recurrent use of cisplatin induces resistance, representing a major hurdle in the treatment of cervical cancer. Our previous study revealed that HP1γ suppresses UBE2L3, an E2 ubiquitin conjugating enzyme, thereby enhancing the stability of tumor suppressor p53 specifically in cervical cancer cells. As a follow-up study of our previous findings, here we have identified that the pharmacological substances, leptomycin B and doxorubicin, can improve the sensitivity of cervical cancer cells to cisplatin inducing HP1γ-mediated elevation of p53. Leptomycin B, which inhibits the nuclear export of HP1γ, increased cisplatin-dependent apoptosis induction by promoting the activation of p53 signaling. We also found that doxorubicin, which induces the DNA damage response, promotes HP1γ-mediated silencing of UBE2L3 and increases p53 stability. These effects resulted from the nuclear translocation and binding of HP1γ on the UBE2L3 promoter. Doxorubicin sensitized the cisplatin-resistant cervical cancer cells, enhancing their p53 levels and rate of apoptosis when administered together with cisplatin. Our findings reveal a therapeutic strategy to target a specific molecular pathway that contributes to p53 degradation for the treatment of patients with cervical cancer, particularly with cisplatin resistance.

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Noninvasive Detection of Early Metabolic Left Ventricular Remodeling in Systemic Hypertension

Cardiology ◽

10.1159/000441276 ◽

2015 ◽

Vol 133 (3) ◽

pp. 157-162 ◽

Cited By ~ 15

Author(s):

Yasmin S. Hamirani ◽

Bijoy K. Kundu ◽

Min Zhong ◽

Andrew McBride ◽

Yinlin Li ◽

...

Keyword(s):

Glucose Uptake ◽

Ventricular Remodeling ◽

Left Ventricular Remodeling ◽

Pressure Overload ◽

Positron Emission Tomography Imaging ◽

Left Ventricular ◽

Systemic Hypertension ◽

Myocardial Glucose Uptake ◽

Positron Emission ◽

Metabolic Remodeling

Objectives: Hypertension (HTN) is a common cause of left ventricular hypertrophy (LVH). Sustained pressure overload induces a permanent myocardial switch from fatty-acid to glucose metabolism. In this study, we tested the hypothesis that metabolic remodeling, characterized by increased myocardial glucose uptake, precedes structural and functional remodeling in HTN-induced LVH. Methods: We recruited 31 patients: 11 with HTN only, 9 with HTN and LVH and 11 normotensive controls without LVH. Transthoracic echocardiography was performed to assess the function, mass, wall thickness and diastolic function of the left ventricle. Positron emission tomography imaging was performed, and the rate of myocardial 2-deoxy-2-[18F]fluoro-D-glucose uptake, Ki, was determined using a 3-compartment kinetic model. Results: The mean Ki values were significantly higher in HTN patients than in those with HTN and LVH (p < 0.001) and in controls (p = 0.003). The unexpected decrease in Ki with LVH may be secondary to a decreased Ki with diastolic dysfunction (DD), 0.039 ± 0.032 versus 0.072 ± 0.013 (p = 0.004). There was also a significant stepwise decrease in Ki with increasing DD grade (p = 0.04). Conclusion: Glucose metabolic remodeling is detectable in hypertensive patients before the development of LVH. Furthermore, lower glucose uptake rates are observed in patients with DD. The mechanism for this last finding requires further investigation.

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The role of an evolutionarily conserved cis-proline in the thioredoxin-like domain of human class Alpha glutathione transferase A1-1

Biochemical Journal ◽

10.1042/bj20021765 ◽

2003 ◽

Vol 372 (1) ◽

pp. 241-246 ◽

Cited By ~ 24

Author(s):

Chris NATHANIEL ◽

Louise A. WALLACE ◽

Jonathan BURKE ◽

Heini W. DIRR

Keyword(s):

Glutathione Transferase ◽

Conformational Stability ◽

Wild Type ◽

Catalytic Function ◽

Evolutionarily Conserved ◽

Glutathione S Transferases ◽

Equilibrium Unfolding ◽

The Stability ◽

Unfolding Kinetics

The thioredoxin-like fold has a βαβαββα topology, and most proteins/domains with this fold have a topologically conserved cis-proline residue at the N-terminus of β-strand 3. This residue plays an important role in the catalytic function and stability of thioredoxin-like proteins, but is reported not to contribute towards the stability of glutathione S-transferases (GSTs) [Allocati, Casalone, Masulli, Caccarelli, Carletti, Parker and Di Ilio (1999) FEBS Lett. 445, 347–350]. In order to further address the role of the cis-proline in the structure, function and stability of GSTs, cis-Pro-56 in human GST (hGST) A1-1 was replaced with a glycine, and the properties of the P56G mutant were compared with those of the wild-type protein. Not only was the catalytic function of the mutant dramatically reduced, so was its conformational stability, as indicated by equilibrium unfolding and unfolding kinetics experiments with urea as denaturant. These findings are discussed in the context of other thioredoxin-like proteins.

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HSP90 is a chaperone for DLK and is required for axon injury signaling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1805351115 ◽

2018 ◽

Vol 115 (42) ◽

pp. E9899-E9908 ◽

Cited By ~ 10

Author(s):

Scott Karney-Grobe ◽

Alexandra Russo ◽

Erin Frey ◽

Jeffrey Milbrandt ◽

Aaron DiAntonio

Keyword(s):

Leucine Zipper ◽

Axon Regeneration ◽

Heat Shock Protein 90 ◽

Hsp90 Inhibitor ◽

Loss Of Function ◽

Hsp90 Inhibition ◽

Axon Injury ◽

Evolutionarily Conserved ◽

The Stability

Peripheral nerve injury induces a robust proregenerative program that drives axon regeneration. While many regeneration-associated genes are known, the mechanisms by which injury activates them are less well-understood. To identify such mechanisms, we performed a loss-of-function pharmacological screen in cultured adult mouse sensory neurons for proteins required to activate this program. Well-characterized inhibitors were present as injury signaling was induced but were removed before axon outgrowth to identify molecules that block induction of the program. Of 480 compounds, 35 prevented injury-induced neurite regrowth. The top hits were inhibitors to heat shock protein 90 (HSP90), a chaperone with no known role in axon injury. HSP90 inhibition blocks injury-induced activation of the proregenerative transcription factor cJun and several regeneration-associated genes. These phenotypes mimic loss of the proregenerative kinase, dual leucine zipper kinase (DLK), a critical neuronal stress sensor that drives axon degeneration, axon regeneration, and cell death. HSP90 is an atypical chaperone that promotes the stability of signaling molecules. HSP90 and DLK show two hallmarks of HSP90–client relationships: (i) HSP90 binds DLK, and (ii) HSP90 inhibition leads to rapid degradation of existing DLK protein. Moreover, HSP90 is required for DLK stability in vivo, where HSP90 inhibitor reduces DLK protein in the sciatic nerve. This phenomenon is evolutionarily conserved in Drosophila. Genetic knockdown of Drosophila HSP90, Hsp83, decreases levels of Drosophila DLK, Wallenda, and blocks Wallenda-dependent synaptic terminal overgrowth and injury signaling. Our findings support the hypothesis that HSP90 chaperones DLK and is required for DLK functions, including proregenerative axon injury signaling.

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Identification of Cdc37 as a Novel Regulator of the Stress-Responsive Mitogen-Activated Protein Kinase

Molecular and Cellular Biology ◽

10.1128/mcb.23.15.5132-5142.2003 ◽

2003 ◽

Vol 23 (15) ◽

pp. 5132-5142 ◽

Cited By ~ 34

Author(s):

Hisashi Tatebe ◽

Kazuhiro Shiozaki

Keyword(s):

Protein Kinase ◽

Protein Kinases ◽

Inflammatory Responses ◽

Cellular Level ◽

Mitogen Activated Protein Kinase ◽

Cellular Survival ◽

Evolutionarily Conserved ◽

Mitogen Activated Protein ◽

Extracellular Stimuli ◽

The Stability

ABSTRACT Eukaryotic cells utilize multiple mitogen-activated protein kinases (MAPKs) to transmit various extracellular stimuli to the nucleus. A subfamily of MAPKs that mediates environmental stress stimuli is also called stress-activated protein kinase (SAPK), which has crucial roles in cellular survival under stress conditions as well as inflammatory responses. Here we report that Cdc37, an evolutionarily conserved kinase-specific chaperone, is a positive regulator of Spc1 SAPK in the fission yeast Schizosaccharomyces pombe. Through a genetic screen, we have identified cdc37 as a mutation that compromises signaling through Spc1 SAPK. The Cdc37 protein physically interacts with Spc1, and the cdc37 mutation affects both the cellular level of the Spc1 protein and stress-induced Spc1 phosphorylation by Wis1 MAPK kinase (MAPKK). Consistently, expression of the stress response genes regulated by the Spc1 pathway is compromised in cdc37 mutant cells. On the other hand, a mutation in Hsp90, which often cooperates with Cdc37 in chaperoning protein kinases, does not affect Spc1 SAPK. These results suggest that Spc1 SAPK is a novel client protein for the Cdc37 chaperone, and the Cdc37 function is important to maintain the stability of the Spc1 protein and to facilitate stress signaling from Wis1 MAPKK to Spc1 SAPK.

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