2-deoxyglucose and ß-hydroxybutyrate fail to attenuate seizures in the betamethasone-NMDA model of infantile spasms.

Infantile spasms (IS) is an epileptic encephalopathy with a poor neurodevelopmental prognosis, and limited, often ineffective treatment options. The effectiveness of metabolic approaches to seizure control is being increasingly shown in a wide variety of epilepsies. This study investigates the efficacy of the glycolysis inhibitor 2-deoxyglucose (2-DG) and the ketone body ß-hydroxybutyrate (BHB) in the betamethasone-NMDA model of rat IS. Prenatal rats were exposed to betamethasone on gestational day 15 (G15) and NMDA on postnatal day 15 (P15). Video-electroencephalography (v-EEG) was used to monitor spasms. NMDA consistently induced hyperflexion spasms associated with interictal sharp-slow wave EEG activity and ictal flattening of EEG signals, reminiscent of hypsarrhythmia and electrodecrement, respectively. 2-DG (500 mg/kg, i.p), BHB (200 mg/kg, i.p.), or both were administered immediately after occurrence of the first spasm. No experimental treatment altered significantly the number, severity, or progression of spasms compared with saline treatment. These data suggest that metabolic inhibition of glycolysis or ketogenesis does not reduce infantile spasms in the NMDA model. The study further validates the betamethasone-NMDA model in terms of its behavioral and electrographic resemblance to human IS and supports its use for preclinical drug screening.

In Vitro Evaluation of the Toxicological Profile and Oxidative Stress of Relevant Diet-Related Advanced Glycation End Products and Related 1,2-Dicarbonyls.

During food processing and storage, and in tissues and fluids under physiological conditions, the Maillard reaction occurs. During this reaction, reactive 1,2-dicarbonyl compounds arise as intermediates that undergo further reactions to form advanced glycation end products (AGEs). Diet is the primary source of exogenous AGEs. Endogenously formed AGEs have been proposed as a risk factor in the pathogenesis of diet-related diseases such as diabetes, insulin resistance, cardiovascular diseases, or chronic disease. AGEs may differently contribute to the diet-related exacerbation of oxidative stress, inflammation, and protein modifications. Here, to understand the contribution of each compound, we tested individually, for the first time, the effect of five 1,2-dicarbonyl compounds 3-deoxyglucosone (3-DG), 3-deoxygalactosone (3-DGal), 3,4-dideoxyglucosone-3-ene (3,4-DGE), glyoxal (GO), and methylglyoxal (MGO) and four different glycated amino acids N-ε-(carboxyethyl)lysine (CEL), N-ε-(carboxymethyl)lysine (CML), methylglyoxal-derived hydroimidazolone-1 (MG-H1), and pyrraline (Pyrr) in a cell line of human keratinocytes (HaCaT). We found that most of the glycated amino acids, i.e., CEL, CML, and MG-H1, did not show any cytotoxicity. At the same time, 1,2-dicarbonyl compounds 3-DGal, 3,4-DGE, GO, and MGO increased the production of reactive oxygen species and induced cell death. MGO induced cell death by apoptosis, whereas 3-DGal and 3,4-DGE induced nuclear translocation of the proinflammatory NF-κB transcription pathway, and the activation of the pyroptosis-related NLRP3 inflammasome cascade. Overall, these results demonstrate the higher toxic impact of 1,2-dicarbonyl compounds on mucosal epithelial cells when compared to glycated amino acids and the selective activation of intracellular signaling pathways involved in the crosstalk mechanisms linking oxidative stress to excessive inflammation.

Enhanced Glycolysis Is Required for Antileishmanial Functions of Neutrophils Upon Infection With Leishmania donovani.

Visceral leishmaniasis (VL) is a fatal parasitic disease if untreated. Treatment options of VL diminish due to emerging drug resistance. Although the principal host cells for the multiplication of Leishmania are macrophages, neutrophils are the first cells infected with the parasites rapidly after parasite inoculation. Leishmania can survive in neutrophils despite the potent antimicrobial effector functions of neutrophils that can eliminate the parasites. Recently, the growing field of immunometabolism provided strong evidence for the therapeutic potential in targeting metabolic processes as a means of controlling immune effector functions. Therefore, the understanding of the immunometabolic profile of neutrophils during Leishmania infection could provide new promising targets for host-directed therapies against VL. To our knowledge, this is the first study addressing the bioenergetics profile of L. donovani-infected primary human neutrophils. Transcriptome analysis of L. donovani-infected neutrophils revealed an early significant upregulation of several glycolytic enzymes. Extracellular flux analysis showed that glycolysis and glycolytic capacity were upregulated in L. donovani-infected neutrophils at 6 h post infection. An increased glucose uptake and accumulation of glycolytic end products were further signs for an elevated glycolytic metabolism in L. donovani-infected neutrophils. At the same time point, oxidative phosphorylation provided NADPH for the oxidative burst but did not contribute to ATP production. Inhibition of glycolysis with 2-DG significantly reduced the survival of L. donovani promastigotes in neutrophils and in culture. However, this reduction was due to a direct antileishmanial effect of 2-DG and not a consequence of enhanced antileishmanial activity of neutrophils. To further address the impact of glucose metabolism during the first days of infection in vivo, we treated C57BL/6 mice with 2-DG prior to infection with L. donovani and assessed the parasite load one day and seven days post infection. Our results show, that seven days post-infection the parasite load of 2-DG treated animals was significantly higher than in mock treated animals. This data indicates that glycolysis serves as major energy source for antimicrobial effector functions against L. donovani. Inhibition of glycolysis abrogates important neutrophil effector functions that are necessary the initial control of Leishmania infection.

Evidence of hypoglycemic anhedonia and modulation by bupropion in rats.

BACKGROUND: Disorders characterized by dysfunction of glucose metabolism are often comorbid with depression. The current study investigated whether a hypoglycemic state caused by 2-deoxy-d-glucose (2-DG) can result in anhedonic behaviors responsive to stimulation of monoamine activity. METHODS: In experiment 1, male Sprague-Dawley rats were tested for maintenance of intra-oral self-administration (IOSA) of a sweet solution after pre-treatment with 300 or 500 mg/kg 2-DG, a blocker of glucose metabolism. Experiment 2 determined whether exposure to an environment previously paired with the effects of 2-DG (0, 200 or 300 mg/kg) can influence IOSA, and whether 2-DG can modify taste reactivity to same sweet solution. Finally, experiment 3 examined whether 0 or 30 mg/kg bupropion, a monoamine-reuptake blocker, would attenuate the effect of 300 mg/kg 2-DG on IOSA and taste reactivity. RESULTS: It was found that 2-DG produced a sustained decrease in IOSA when animals were tested drug-free. This decrease in IOSA did not appear linked to place conditioning or to alterations in taste reactivity, and it was partially normalized by pre-treatment with bupropion. CONCLUSIONS: Taken together, these results in rats suggest that rapid hypoglycemia can induce an anhedonic state characterized by impaired consummatory responses to nutritional incentive stimuli and that can be alleviated by the antidepressant bupropion.

Spontaneous mutations that confer resistance to 2-deoxyglucose act through Hxk2 and Snf1 pathways to regulate gene expression and HXT endocytosis.

Yeast and fast-growing human tumor cells share metabolic similarities in that both cells use fermentation of glucose for energy and both are highly sensitive to the glucose analog 2-deoxyglucose. Spontaneous mutations in S. cerevisiae that conferred resistance to 2-deoxyglucose were identified by whole genome sequencing. Missense alleles of the HXK2, REG1, GLC7 and SNF1 genes were shown to confer significant resistance to 2-deoxyglucose and all had the potential to alter the activity and or target selection of the Snf1 kinase signaling pathway. All three missense alleles in HXK2 resulted in significantly reduced catalytic activity. Addition of 2DG promotes endocytosis of the glucose transporter Hxt3. All but one of the 2DG-resistant strains reduced the 2DG-mediated hexose transporter endocytosis by increasing plasma membrane occupancy of the Hxt3 protein. Increased expression of the DOG (deoxyglucose) phosphatases has been associated with resistance to 2-deoxyglucose. Expression of both the DOG1 and DOG2 mRNA was elevated after treatment with 2-deoxyglucose but induction of these genes is not associated with 2DG-resistance. RNAseq analysis of the transcriptional response to 2DG showed large scale, genome-wide changes in mRNA abundance that were greatly reduced in the 2DG resistant strains. These findings suggest the common adaptive response to 2DG is to limit the magnitude of the response. Genetic studies of 2DG resistance using the dominant SNF1-G53R allele in cells that are genetically compromised in both the endocytosis and DOG pathways suggest that at least one more mechanism for conferring resistance to this glucose analog remains to be discovered.

Safety, Biodistribution, and Dosimetry of 123I-6-Deoxy-6-Iodo-D-Glucose, a Tracer of Glucose Transport, in Healthy and Diabetic Volunteers.

PURPOSE: Insulin resistance is a key feature of the metabolic syndrome and type 2 diabetes, in which noninvasive assessment is not currently allowed by any methodology. We previously validated an iodinated tracer of glucose transport (6DIG) and a new methodology for the in vivo quantification of cardiac insulin resistance in rodents. The aim of this study was to investigate the safety, biodistribution, and radiation dosimetry of this method using I-6DIG in 5 healthy and 6 diabetic volunteers. METHODS: The collection of adverse effects (AEs) and medical supervision of vital parameters and biological variables allowed the safety evaluation. Biodistribution was studied by sequentially acquiring whole-body images at 1, 2, 4, 8, and 24 hours postinjection. The total number of disintegrations in each organ normalized to the injected activity was calculated as the area under the time-activity curves. Dosimetry calculations were performed using OLINDA/EXM. RESULTS: No major adverse events were observed. The average dose corresponding to the 2 injections of I-6DIG used in the protocol was 182.1 ± 7.5 MBq. A fast blood clearance of I-6DIG was observed. The main route of elimination was urinary, with greater than 50% of urine activity over 24 hours. No blood or urine metabolite was detected. I-6DIG accumulation mostly occurred in elimination organs such as kidneys and liver. Mean radiation dosimetry calculations indicated an effective whole-body absorbed dose of 3.35 ± 0.57 mSv for the whole procedure. CONCLUSIONS: I-6DIG was well tolerated in human with a dosimetry profile comparable to that of other commonly used iodinated tracers, thereby allowing further clinical development of the tracer.

Rescue of 2-Deoxyglucose Side Effects by Ketogenic Diet.

Cancer metabolism is characterized by extensive glucose consumption through aerobic glycolysis. No effective therapy exploiting this cancer trait has emerged so far, in part, due to the substantial side effects of the investigated drugs. In this study, we examined the side effects of a combination of isocaloric ketogenic diet (KD) with the glycolysis inhibitor 2-deoxyglucose (2-DG). Two groups of eight athymic nude mice were either fed a standard diet (SD) or a caloric unrestricted KD with a ratio of 4 g fat to 1 g protein/carbohydrate. 2-DG was investigated in commonly employed doses of 0.5 to 4 g/kg and up to 8 g/kg. Ketosis was achieved under KD (ketone bodies: SD 0.5 ± 0.14 mmol/L, KD 1.38 ± 0.28 mmol/L, p < 0.01). The intraperitoneal application of 4 g/kg of 2-DG caused a significant increase in blood glucose, which was not prevented by KD. Sedation after the 2-DG treatment was observed and a behavioral test of spontaneous motion showed that KD reduced the sedation by 2-DG (p < 0.001). A 2-DG dose escalation to 8 g/kg was lethal for 50% of the mice in the SD and for 0% of the mice in the KD group (p < 0.01). A long-term combination of KD and an oral 1 or 2 g 2-DG/kg was well-tolerated. In conclusion, KD reduces the sedative effects of 2-DG and dramatically increases the maximum tolerated dose of 2-DG. A continued combination of KD and anti-glycolytic therapy is feasible. This is, to our knowledge, the first demonstration of increased tolerance to glycolysis inhibition by KD.

Defective glycolysis and the use of 2-deoxy-D-glucose in polycystic kidney disease: from animal models to humans.

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited renal disease characterized by bilateral renal cyst formation. ADPKD is one of the most common rare disorders, accounting for ~10% of all patients with end-stage renal disease (ESRD). ADPKD is a chronic disorder in which the gradual expansion of cysts that form in a minority of nephrons eventually causes loss of renal function due to the compression and degeneration of the surrounding normal parenchyma. Numerous deranged pathways have been identified in the cyst-lining epithelia, prompting the design of potential therapies. Several of these potential treatments have proved effective in slowing down disease progression in pre-clinical animal studies, while only one has subsequently been proven to effectively slow down disease progression in patients, and it has recently been approved for therapy in Europe, Canada and Japan. Among the affected cellular functions and pathways, recent investigations have described metabolic derangement in ADPKD as a major trait offering additional opportunities for targeted therapies. In particular, increased aerobic glycolysis (the Warburg effect) has been described as a prominent feature of ADPKD kidneys and its inhibition using the glucose analogue 2-deoxy-D-glucose (2DG) proved effective in slowing down disease progression in preclinical models of the disease. At the same time, previous clinical experiences have been reported with 2DG, showing that this compound is well tolerated in humans with minimal and reversible side effects. In this work, we review the literature and speculate that 2DG could be a good candidate for a clinical trial in humans affected by ADPKD.

Acute Reduction of Incretin Effect and Glucose Intolerance in Rats by Single Intragastric Administration of 3-deoxyglucosone.

Secretion of glucagon-like peptide-1 has been suggested to be impaired in T2DM and in conditions associated with hyperglycemia. 3-Deoxyglucosone, a dietary composition, has been suggested as an independent factor for the development of prediabetes. A-pathophysiological very high condition of 3DG concentrations administered i. v. induced acute glucose intolerance in rats. In this study, to examine the acute effects of single intragastric administration of 3DG at dose of potentially single-meal intake on plasma glucose, insulin, glucagon, total GLP-1 and total GIP levels in response to a glucose load, OGTT was performed immediately in normal Kunming mice or Sprague-Dawleys rats after 3DG administration. GLP-1 secretion, intracellular cAMP levels and 2-NBDG uptake were examined in STC-1 cells exposured to 3DG. In rats, 20 mg/kg 3DG i.g. (3DG-20 i.g.) impaired glucose tolerance (P<0.05) with increased AUC (1 070±105.2 vs. 918.0±91.20, P<0.05). The mice treated with 3DG-20 i.g. exhibited a similar effect, independent of the effect of plasma 3DG concentration. 3DG-20 i.g. treatment reduced plasma insulin concentrations with decreased AUC (3 552±300.2 vs. 4 715±420.5, P<0.05) in rats whereas plasma glucagon levels were not significantly different. These changes occurred in conjunction with decreased plasma GLP-1 and GIP levels (P<0.05). Furthermore, non-cytotoxic 3DG concentrations directly reduced GLP-1 secretion in STC-1, at least in part, by decreasing intracellular cAMP level and glucose uptake. We demonstrated for the first time that single intragastric administration of 3DG resulted in acute reduction of incretin effect and glucose intolerance, which was associated with a decrease in the biological function of GLP-1 by decreasing GLP-1 secretion.

SIRT1 suppresses self-renewal of adult hippocampal neural stem cells.

The balance between self-renewal and differentiation of adult neural stem cells (aNSCs) is essential for the maintenance of the aNSC reservoir and the continuous supply of new neurons, but how this balance is fine-tuned in the adult brain is not fully understood. Here, we investigate the role of SIRT1, an important metabolic sensor and epigenetic repressor, in regulating adult hippocampal neurogenesis in mice. We found that there was an increase in SIRT1 expression during aNSC differentiation. In Sirt1 knockout (KO) mice, as well as in brain-specific and inducible stem cell-specific conditional KO mice, the proliferation and self-renewal rates of aNSCs in vivo were elevated. Proliferation and self-renewal rates of aNSCs and adult neural progenitor cells (aNPCs) were also elevated in neurospheres derived from Sirt1 KO mice and were suppressed by the SIRT1 agonist resveratrol in neurospheres from wild-type mice. In cultured neurospheres, 2-deoxy-D-glucose-induced metabolic stress suppressed aNSC/aNPC proliferation, and this effect was mediated in part by elevating SIRT1 activity. Microarray and biochemical analysis of neurospheres suggested an inhibitory effect of SIRT1 on Notch signaling in aNSCs/aNPCs. Inhibition of Notch signaling by a γ-secretase inhibitor also largely abolished the increased aNSC/aNPC proliferation caused by Sirt1 deletion. Together, these findings indicate that SIRT1 is an important regulator of aNSC/aNPC self-renewal and a potential mediator of the effect of metabolic changes.

Mitochondria-targeted antioxidant and glycolysis inhibition: synergistic therapy in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. Mito-carboxy proxyl (Mito-CP), a lipophilic cationic nitroxide, accumulates in the mitochondria because of the large negative transmembrane potential. Studies have shown that these agents act by disrupting the energy-producing mechanism, inducing mitochondrial-mediated apoptosis, and also enhancing the action of other chemotherapeutic agents in cancer cells. We hypothesized that the combination of Mito-CP and glycolysis inhibitor, 2-deoxyglucose (2-DG), would synergistically inhibit HCC in vitro. HepG2 cells and primary hepatocytes were treated with various combinations of Mito-CP and 2-DG. Cell cytotoxicity was measured using the methylthiazolyldiphenyl-tetrazolium bromide assay and ATP bioluminescence assay. In addition, caspase 3/7 enzymatic activity was examined after treatment. Mito-CP and 2-DG induced synergistic cytotoxicity in HepG2 cells in a dose-dependent and time-dependent manner, whereas primary cells remained viable and unaffected after treatment. The intracellular ATP levels of HepG2 cells were suppressed within 6 h of combination treatment, whereas primary cells maintained higher levels of ATP. Dose-dependent increases in caspase 3/7 activity occurred in HepG2 cells in a time-dependent manner, showing the initiation of cell death through the apoptotic pathway. These findings indicate that a combination of Mito-CP and 2-DG effectively inhibits HCC growth in vitro. The increase in caspase 3/7 activity supports the occurrence of 2-DG-induced and Mito-CP-induced apoptotic death in HCC. The inability of the compounds to induce cytotoxicity or suppress the production of ATP in primary hepatocytes provides a selective and synergistic approach for the treatment of HCC.

Neurochemical codes of sympathetic preganglionic neurons activated by glucoprivation.

Glucoprivation or hypoglycemia induces a range of counterregulatory responses, including glucose mobilization, reduced glucose utilization, and de novo glucose synthesis. These responses are mediated in part by the sympathetic nervous system. The aim of this study was to determine the chemical codes of sympathetic preganglionic neurons (SPN) activated by glucoprivation, induced by 2-deoxy-D-glucose (2DG). SPN controlling the adrenal glands and celiac ganglia, which ultimately can innervate the liver and pancreas, were targeted together with the superior cervical ganglia (control). 23.9% ± 1.3% of SPN in the T4-T11 region contained c-Fos immunoreactivity following 2DG; 70.3% ± 1.8% of SPN innervating the adrenal glands and 37.4% ± 3% of SPN innervating celiac ganglia were activated. 14.8% ± 3.5% of SPN (C8-T3) innervating superior cervical ganglia were activated. In the C8-T3 region 55% ± 10% of SPN activated contained PPCART, with only 12% ± 3% expressing PPE mRNA, whereas, in the T4-T11 region, 78% ± 4% contained PPE, with only 6.0% ± 0.6% expressing PPCART mRNA. Thus CART is not involved in glucose mobilization. Two chemically distinct populations of SPN (PPE⁺ 57.4% ± 5%, PPE⁻ ∼40%) were identified to regulate adrenaline release in response to glucoprivation. Multiple chemically distinct SPN populations innervating a specific target could suggest their graded recruitment. The two distinct populations of SPN (PPE⁺ 67.6% ± 9%, PPE⁻ ∼30%) projecting to celiac ganglia activated by glucoprivation could direct pancreatic and hepatic or other counterregulatory responses. Nearly all SPN that expressed PPE mRNA and projected to the adrenal glands or celiac ganglia were activated, suggesting a role for the inhibitory peptide enkephalin in responses evoked by glucoprivation.

Protective effects of dietary 1,5-anhydro-D-glucitol as a blood glucose regulator in diabetes and metabolic syndrome.

1,5-Anhydro-D-glucitol (1,5-AG) is fairly widespread in food products. It is also one of the major polyols in the human body, and its concentration is homeostatically regulated. We report here on the beneficial effects of 1,5-AG in preventing hyperglycemia and its role in improving metabolic syndrome. The findings revealed that it does not affect blood glucose levels itself under normal conditions but clearly has a suppressive effect on the levels of dietary sugars, such as glucose, maltose, and sucrose. A long-term administration study revealed that feeding db/db diabetic mice 3% 1,5-AG for 8 weeks significantly decreased blood glucose levels compared to untreated mice (339 ± 30 versus 438 ± 34 mg/dL; p < 0.05). Furthermore, this treatment also significantly suppressed serum cholesterol levels (110.2 ± 18.0 versus 168.4 ± 9.8 mg/dL; p < 0.01). 1,5-AG did not inhibit intestinal α-glucosidase activities but regulated liver glucose levels via affecting both the glycogenolysis and gluconeogenesis pathways. Furthermore, the oral administration of 1,5-AG significantly increased urinary glucose excretion in hyperglycemic conditions. These results clearly suggest that dietary 1,5-AG acts as a modulator of glucose levels in hyperglycemia. 1,5-AG therefore represents a new class of promising functional sweeteners, where the daily consumption of 1,5-AG with meals could inhibit the progress of hyperglycemia and metabolic syndrome.

A phase I dose-escalation trial of 2-deoxy-D-glucose alone or combined with docetaxel in patients with advanced solid tumors.

PURPOSE: This phase I trial was initiated to evaluate the safety, pharmacokinetics (PK) and maximum tolerated dose (MTD) of the glycolytic inhibitor, 2-deoxy-D-glucose (2DG) in combination with docetaxel, in patients with advanced solid tumors. METHODS: A modified accelerated titration design was used. 2DG was administered orally once daily for 7 days every other week starting at a dose of 2 mg/kg and docetaxel was administered intravenously at 30 mg/m(2) for 3 of every 4 weeks beginning on day 1 of week 2. Following the completion of dose escalation, cohorts of patients were then treated with 2DG for 21 days or every day of each 4-week cycle for up to 12 cycles. RESULTS: Thirty-four patients were enrolled: 21 on every other week, 6 on a 21 of 28-day cycle and 7 on the continuous 2DG dosing schedule. There were no dose-limiting toxicities which met the MTD criteria. The most common adverse events were fatigue, sweating, dizziness and nausea mimicking the hypoglycemic symptoms expected from 2DG administration. Therefore, 63 mg/kg was selected as the clinically tolerable dose. The most significant adverse effects noted at 63-88 mg/kg doses were reversible hyperglycemia (100 %), gastrointestinal bleeding (6 %) and reversible grade 3 QTc prolongation (22 %). Eleven patients (32 %) had stable disease, 1 patient (3 %) partial response and 22 patients (66 %) progressive disease as their best response. There was no PK interaction between 2DG and docetaxel. CONCLUSION: The recommended dose of 2DG in combination with weekly docetaxel is 63 mg/kg/day with tolerable adverse effects.

Ca2+/calmodulin-dependent protein kinase kinase is not involved in hypothalamic AMP-activated protein kinase activation by neuroglucopenia.

Hypoglycemia and neuroglucopenia stimulate AMP-activated protein kinase (AMPK) activity in the hypothalamus and this plays an important role in the counterregulatory responses, i.e. increased food intake and secretion of glucagon, corticosterone and catecholamines. Several upstream kinases that activate AMPK have been identified including Ca(2+)/Calmodulin-dependent protein kinase kinase (CaMKK), which is highly expressed in neurons. However, the involvement of CaMKK in neuroglucopenia-induced activation of AMPK in the hypothalamus has not been tested. To determine whether neuroglucopenia-induced AMPK activation is mediated by CaMKK, we tested whether STO-609 (STO), a CaMKK inhibitor, would block the effects of 2-deoxy-D-glucose (2DG)-induced neuroglucopenia both ex vivo on brain sections and in vivo. Preincubation of rat brain sections with STO blocked KCl-induced α1 and α2-AMPK activation but did not affect AMPK activation by 2DG in the medio-basal hypothalamus. To confirm these findings in vivo, STO was pre-administrated intracerebroventricularly (ICV) in rats 30 min before 2DG ICV injection (40 µmol) to induce neuroglucopenia. 2DG-induced neuroglucopenia lead to a significant increase in glycemia and food intake compared to saline-injected control rats. ICV pre-administration of STO (5, 20 or 50 nmol) did not affect 2DG-induced hyperglycemia and food intake. Importantly, activation of hypothalamic α1 and α2-AMPK by 2DG was not affected by ICV pre-administration of STO. In conclusion, activation of hypothalamic AMPK by 2DG-induced neuroglucopenia is not mediated by CaMKK.

Behavioral, cognitive, and safety profile of 2-deoxy-2-glucose (2DG) in adult rats.

2-Deoxy-D-glucose (2DG), a glucose analog that transiently inhibits glycolysis, has anticonvulsant and antiepileptic disease-modifying properties in experimental in vivo models of seizures and epilepsy. Here we evaluated the effects of 2DG across the range of doses (50-500mg/kg i.p.) shown previously to exert anticonvulsant and antiepileptic effects in rats, on spatial learning and memory using the Morris water maze and on exploratory behavior using the open field test. For water maze testing, both acute and chronic protocols were tested. For acute testing, 2DG was injected for 15min prior to the water maze trial only on testing days. For chronic testing, 2DG was injected daily for 14days before water maze testing began. Neither protocol altered the latency to platform acquisition or retention of platform location by the probe test. For open field testing, 2DG was given at doses of 50-250mg/kg 15 or 30min prior to testing on each testing day. When given 30min prior to testing, exploratory activity in the open field was transiently and reversibly decreased by 2DG at doses of 250mg/kg/day but there were no effects on open field activity at 50mg/kg/day. When given 15min prior to testing, 2DG decreased exploratory activity in a dose-dependent fashion at both 50 and 250mg/kg. There were no toxic effects of 2DG at doses of 500mg/kg/day on body weight or general health. In summary, 2DG is well tolerated at doses associated with anticonvulsant and antiepileptic effects, supporting its potential as an anticonvulsant and antiepileptic agent with a novel mechanism of action.

Protein phosphorylation on tyrosine restores expression and glycosylation of cyclooxygenase-2 by 2-deoxy-D-glucose-caused endoplasmic reticulum stress in rabbit articular chondrocyte.

2-deoxy-D-glucose(2DG)-caused endoplasmic reticulum (ER) stress inhibits protein phosphorylation at tyrosine residues. However, the accurate regulatory mechanisms, which determine the inflammatory response of chondrocytes to ER stress via protein tyrosine phosphorylation, have not been systematically evaluated. Thus, in this study, we examined whether protein phosphorylation at tyrosine residues can modulate the expression and glycosylation of COX-2, which is reduced by 2DG-induced ER stress. We observed that protein tyrosine phosphatase (PTP) inhibitors, sodium orthovanadate (SOV), and phenylarsine oxide (PAO) significantly decreased expression of ER stress inducible proteins, glucose-regulated protein 94 (GRP94), and CCAAT/enhancer-binding-protein- related gene (GADD153), which was induced by 2DG. In addition, we demonstrated that SOV and PAO noticeably restored the expression and glycosylation of COX-2 after treatment with 2DG. These results suggest that protein phosphorylation of tyrosine residues plays an important role in the regulation of expression and glycosylation during 2DG-induced ER stress in rabbit articular chondrocytes.

Combining radioimmunotherapy with antihypoxia therapy 2-deoxy-D-glucose results in reduction of therapeutic efficacy.

PURPOSE: The efficacy of solid tumor radioimmunotherapy is reduced by heterogeneous tumor distribution of the radionuclide, with dose mainly deposited in the normoxic region and by the relative radioresistance of hypoxic tumor cells. In an attempt to overcome these challenges, radioimmunotherapy was combined with 2-deoxy-d-glucose (2DG), a hypoxia-selective cytotoxic inhibitor of glucose metabolism. EXPERIMENTAL DESIGN: In vitro toxicity of 2DG in LS174T cultures was tested using a colony-forming assay. The effect of combining 2DG with radioimmunotherapy in vivo was tested by administering radiolabeled anti-carcinoembryonic antigen antibody ([(131)I]A5B7 IgG1 whole monoclonal) to nude mice bearing s.c. LS174T tumors, followed by 10 daily injections of 2DG (2.0 g/kg). Tumors were measured to assess therapeutic efficacy. RESULTS: Data from in vitro studies confirmed 2DG cytotoxicity in this cell line. Greater toxicity was observed under standard laboratory conditions and in hypoxic cultures than at intermediate, physiologically relevant levels of glucose and oxygen. Alone, 2DG had no effect on in vivo tumor growth (P = 0.377 compared with saline-treated controls). Combination of radioimmunotherapy with 2DG reduced the therapeutic effect of radioimmunotherapy (e.g., 150 microCi (131)I alone mean survival time, 48.33 +/- 16.83 days; combined with 2DG, 30.67 +/- 5.62 days, P = 0.038). CONCLUSIONS: The combination investigated had a detrimental effect on survival. It is suggested that a cellular metabolic response to more aggressive therapy, previously reported in vitro, caused this. The results of this study have implications for the clinical application of combined cancer therapies with an antimetabolic modality component.

3,4-DGE is important for side effects in peritoneal dialysis what about its role in diabetes.

Breakdown of glucose under physiological conditions gives rise to glucose degradation products (GDPs). GDPs are also formed during heat sterilization of glucose-containing peritoneal dialysis fluids (PD-fluids). In PD-fluids GDPs have been shown in many different in vitro assays to be responsible for adverse effects such as growth inhibition, and impaired leukocyte function and impaired wound healing of peritoneal mesothelial cells. They have been linked to changes in the peritoneal membrane as well as to the decline in residual renal function of PD-patients. In diabetes one of the GDPs, 3-deoxyglucosone (3-DG), has been proposed as responsible for side-effects rather the glucose itself. 3,4-dideoxyglucosone-3-ene (3,4-DGE) was recently identified as the most bio-reactive GDP in PD-fluids. It exists in equilibrium with a pool of precursors, consisting of 3-DG but also of other hitherto unidentified GDPs. In PD-fluids the concentration of GDPs in this pool is 10-20 times as high as that of 3,4-DGE. In vitro 3,4-DGE induces caspase-dependent apoptosis of neutrophils and peripheral blood mononuclear cells. Such induction may explain immunosuppressive properties of 3,4-DGE and contribute to an impaired peritoneal antibacterial defense. 3,4-DGE also induces renal cell apoptosis. This may explain the better preservation of residual renal function in PD patients not exposed to GDPs. The concentration of 3-DG increases with worsening glycemic control and has been implicated in the genesis of diabetic microangiopathy. As 3,4-DGE is much more bio-reactive than 3-DG and as it may be easily recruited from the pool, it seems probable that 3,4-DGE is the molecule involved in the diabetic lesions rather than 3-DG itself. Thus, 3,4-DGE might contribute to diabetic nephropathy and to the impaired antibacterial defenses in diabetics. Unraveling of the pool dynamics of the GDPs and the molecular mechanisms of GDP-mediated cell injury may provide new therapeutic insights in PD and diabetes.

Optimizing cancer radiotherapy with 2-deoxy-d-glucose dose escalation studies in patients with glioblastoma multiforme.

BACKGROUND AND PURPOSE: Higher rates of glucose utilization and glycolysis generally correlate with poor prognosis in several types of malignant tumors. Own earlier studies on model systems demonstrated that the nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DG) could enhance the efficacy of radiotherapy in a dose-dependent manner by selectively sensitizing cancer cells while protecting normal cells. Phase I/II clinical trials indicated that the combination of 2-DG, at an oral dose of 200 mg/kg body weight (BW), with large fractions of gamma-radiation was well tolerated in cerebral glioma patients. Since higher 2-DG doses are expected to improve the therapeutic gain, present studies were undertaken to examine the tolerance and safety of escalating 2-DG dose during combined treatment (2-DG + radiotherapy) in glioblastoma multiforme patients. PATIENTS AND METHODS: Untreated patients with histologically proven glioblastoma multiforme (WHO criteria) were included in the study. Seven weekly fractions of (60)Co gamma-rays (5 Gy/fraction) were delivered to the tumor volume (presurgical CT/MRI evaluation) plus 3 cm margin. Escalating 2-DG doses (200-250-300 mg/kg BW) were administered orally 30 min before irradiation after overnight fasting. Acute toxicity and tolerance were studied by monitoring the vital parameters and side effects. Late radiation damage and treatment responses were studied radiologically and clinically in surviving patients. RESULTS: Transient side effects similar to hypoglycemia were observed in most of the patients. Tolerance and patient compliance to the combined treatment were very good up to a 2-DG dose of 250 mg/kg BW. However, at the higher dose of 300 mg/kg BW, two out of six patients were very restless and could not complete treatment, though significant changes in the vital parameters were not observed even at this dose. No significant damage to the normal brain tissue was observed during follow-up in seven out of ten patients who received complete treatment and survived between 11 and 46 months after treatment. CONCLUSION: Oral administration of 2-DG combined with large fractions of radiation (5 Gy/fraction/week) is safe and could be tolerated in glioblastoma patients without any acute toxicity and late radiation damage to the normal brain. Further clinical studies to evaluate the efficacy of the combined treatment are warranted.