Effect Of 2DG Research Articles

Effect of 2-Deoxyglucose, a Glycolytic Inhibitor, on the ATP Levels and Viability of B Lymphocytes from Subjects with Chronic Lymphocytic Leukemia (CLL).

One hallmark of tumor cells is a high rate of glycolysis, which underlies the utility of the glucose analog, 2-[18]fluoro-2-deoxyglucose for PET imaging of solid tumors. The glucose analog, 2-deoxyglucose (2DG), inhibits glycolysis, and is predicted to decrease the viability of tumor cells, which are primarily dependent on the glycolytic pathway for ATP generation. We have recently shown that 2DG enhances the efficacy of either adriamycin or paclitaxel in delaying tumor growth in mouse xenograft cancer models (Maschek et al, Cancer Res 64 (2004): 31). We are currently conducting a phase 1 clinical trial to examine the safety of a combination administration of 2DG and Taxotere in patients with solid tumors. The goal of the current study is to measure the extent to which 2DG inhibits energy production and, consequently, reduces viability of leukemic cells. Heparinized blood was obtained from four subjects with a confirmed diagnosis of CLL (peripheral lymphocyte blood count ranged from 5,000–24,000/mm3), with an additional sample drawn from each subject two weeks later for replicate determinations. The mononuclear cell fraction (predominantly B cells) was isolated using Histopaque. Subsequent treatment of isolated CLL cells with 2DG (164 μg/ml) at 37°C (in the presence of 0.5 mM glucose) resulted in a 20–30% decrease in cellular ATP levels after 1 hr (compared with untreated cells) and a 60–70% decrease in ATP levels after 24 hrs. In the presence of 5 mM glucose, incubation of CLL cells with 2DG elicited a 5–10% decrease in ATP at 1 hr and 15–20% reduction in ATP levels at 24 hrs. The effect of 2DG on cell viability was assessed using Alamar Blue. Treatment of CLL cells with 2DG (164 μg/ml, in the presence of 0.5 mM glucose) resulted in a 50% loss in cell viability at 24 hrs (compared with untreated cells at the same time point), and a 70% loss at 48 hrs. In the presence of 5 mM glucose, the effect of 2DG was more modest. At 24 hrs, there was a 20% loss of cell viability and a 30–50% loss at 48 hrs. In conclusion, these results demonstrate that in vitro treatment of CLL B cells with 2DG decreases cellular ATP levels, ultimately resulting in a loss of cell viability. Updated results with samples from additional CLL subjects will be presented, together with an assessment of the therapeutic potential of 2DG for the treatment of CLL.

Nuclear all-trans retinoic acid receptor status in rat liver: A comparison of effects of three different stressors-immobilization, laparotomy, and 2-deoxy-D-glucose

Retinoic acids and their cognate nuclear receptors exert a substantial regulatory role in cell growth and development as well as in the neuroendocrine system. These effects are primarily mediated by all-trans retinoic acid receptors (RARs), members of the steroid/thyroid hormone receptor superfamily of ligand inducible transcription factors. The present study was undertaken in order to compare the effects of immobilization stress (IMO), laparotomy, and 2-deoxy-D-glucose (2DG)-induced intracellular glucopenia on both nuclear RAR affinity and concentration in the rat liver. IMO when compared to non-stressed group of rats, significantly reduced the RAR maximal binding capacity (B max) in liver, with the equilibrium association constant (K a) remaining unchanged. No significant changes of the RAR B max and the K a, were observed in liver of rats that underwent laparotomy. In contrast, a single dose of 2DG (500 mg kg ) resulted in a significant increase of the RAR B max, 10 h after 2DG application, with the K max remaining unchanged. Shorter intervals, 1 or 5 h after 2DG application were ineffective on both the RAR B max and K a. In the 2DG-adapted rats (6 doses of 2 DG, 500 mg kg ; 1 dose/day), decapitated 24 h after the last 2DG dose, the RAR B max was found significantly higher when compared to control group of animals. No further effect of the next dose of 2DG to repeatedly injected rats on the RAR B max and K a was observed in animals killed 5 h after the seventh dose of 2DG. 2DG-induced intracellular glucopenia markedly up-regulates RARs in liver, but does not change the affinity of the receptor. Thus, the effect of 2DG on RAR concentration in liver specifically differs from that of IMO or laparotomy.

Inhibitors of glycolytic metabolism affect neurulation‐staged mouse conceptuses in vitro

In order to evaluate the apparent discordance between altered glucose metabolism and embryonic energy production, the effects of inhibitors of glucose utilization on morphological development and biochemical changes in mouse embryos in culture were evaluated. Day 9 ICR mouse conceptuses having 3-6 pairs of somites were prepared for culture as previously described. 2-Deoxyglucose (2DG) produced a concentration-dependent effect on development. A 25 microM 2DG concentration did not induce neural tube closure defects (NTDs) but 100 microM, 100% of embryos exhibited this defect. A 17% reduction in the rate of lactate production by the conceptus was produced by a 24-hr exposure period to 100 microM 2DG. Iodoacetate, which inhibits glyceraldehyde-3-phosphate dehydrogenase in adult tissues, produced high rates of NTDs at concentrations > or = 2.5 microM. Following a 24 hour exposure to iodoacetate, lactate production was inhibited at 10 and 25 microM. The effects of 2DG on embryonic ATP content were assessed to test the hypothesis that effects on glucose utilization would effect embryonic ATP content. Despite using 2DG concentrations that alter development and inhibit glycolysis, there were no effects on whole embryo or visceral yolk sac (VYS) ATP content. However, when the embryo was divided into regions, there was a specific reduction in ATP content in the head following a 24-hr exposure period. No effect of 2DG on head ATP content was produced after 12 hr of exposure. To determine if there were region specific differences in 2DG uptake and distribution that could account for the differential effects of 2DG on ATP content, 14C-2DG accumulation in different regions of the embryo and VYS was determined over the 24-hr culture period. The uptake of 2DG was dependent on the medium 2DG concentration and suggested a higher accumulation in regions with decreased ATP. However, when the uptake was monitored for a 1-hr period after a 24-hr exposure, there was no region specific differences in 2DG uptake. These studies further document the adverse developmental effects of inhibitors of glucose utilization during the early stage of neurulation. The biochemical mechanism for induction of these defects is unclear, but an effect on ATP content does not appear to be solely responsible for the dysmorphogenesis.

The effect of cellular glucoprivation on skin temperature regulation in the rat

Studies were undertaken to determine the effects of cellular glucoprivation on temperature responses in morphine-addicted and placebo-treated rats and to compare these responses to those observed during naloxone-precipitated morphine withdrawal. Naloxone caused a tail skin temperature (TST) response of 5.7 ± 0.5°C in morphine-dependent rats. Intraperitoneal administration 2-deoxyglucose (2DG) caused TST responses in placebo-treated and morphine-dependent rats of 4.8 ± 0.6 and 6.2 ± 0.5°C, respectively. These data indicate that the activation of the sympathetic nervous system by cellular glucoprivation causes a TST response which is equivalent in magnitude to that induced by precipitating withdrawal with naloxone. This effect of 2DG appears to be mediated by the brain, since icv administration of 2DG caused a TST response, similar to that induced by naloxone treatment of morphine-dependent rats. Collectively, these data suggest that a TST increase is a component of the response of rats to local brain glucoprivation induced by 2DG.

Naloxone decreases centrally induced hyperglycemia in dogs. Evidence for an opioid role in glucose homeostasis.

Intracerebroventricular (ICV) instillation of morphine and beta-endorphin causes centrally induced hyperglycemia. Locally active, endogenous opioids in the central nervous system may, therefore, also be involved in the elevation of blood sugar. This possibility was tested by examining the glucoregulatory response to central glucoprivation induced by ICV administration of 2-deoxy-D-glucose (2DG) in dogs. Administration of 2DG resulted in a rise in plasma glucose and immunoreactive glucagon (IRG) of 108 +/- 19 mg/dl and 70 +/- 20 pg/ml, respectively. These changes were attenuated by the simultaneous central infusion of the opiate antagonist naloxone: plasma glucose levels increased by 77 +/- 14 mg/dl and IRG by 43 +/- 3 pg/ml, both significantly different from the effect of 2DG alone (P less than 0.05-0.01). These findings suggest that opiate receptors participate in the counterregulatory response to central glucoprivation. They also provide a mechanism by which endogenous opioid peptides may play a role in the central regulation of glucose homeostasis.

Physiological and behavioral responses to glucoprivation in the golden hamster

Golden hamsters failed to increase their food intake following food deprivation alone or in combination with insulin or 2-deoxy-D-glucose (2DG) treatment. 2DG also failed to induce feeding in hamsters tested at night. In this latter experiment, there was no effect of 2DG on wheel running or general alertness. Insulin administration significantly decreased plasma levels of glucose and free fatty acids (FFA). 2DG treatment produced a dose-related hyperglycemia associated with increased ketone levels. These data are discussed in terms of cerebral energy status and its relation to food intake and physiological responses.

Epithelial cell motility: the effect of 2-deoxyglucose on cell migration, ATP production, and the structure of the cytoplasmic ground substance in lamellipodia of epithelial cells in culture.

Using a line of epithelial cells (SCCA5) derived from a spontaneous rat carcinoma, the glucose analogue 2-deoxyglucose (2DG) has been shown by time-lapse cinemicrography to produce a cessation of motility by 1 hour that can be reversed by replacement of the 2DG, and does not occur in equivalent media with or without glucose or in 2DG-containing media with added pyruvate and citrate. The effect on the cells at the edge of an epithelial island is to prevent the formation of new lamellipodia and produce a progressive retraction and condensation of lamellipodia already present. This effect of 2DG on motility corresponds with a significant reduction in the level of ATP that is partially restored after 30 minutes in the recovery incubation. Only a slight reduction in protein synthesis occurs in the presence of 2DG. The external morphology and the cytoplasmic ground substance of the cells were studied by scanning electron microscopy and high voltage electron microscopy respectively. It was found that after incubation in 2DG for 1 hour the outline of the free edges of the cells was distorted resulting in redistribution of microvilli, condensation of cytoplasm into strands, and irregular projections from the edges of residual lamellipodia. The structure of the cytoplasmic ground substance in lamellipodia from cells incubated in 2DG for 3 hours was distinctly different from that in cells incubated for 3 hours in 2DG then recovered for 25 minutes, or in cells incubated in glucose-containing medium for 3 hours. In the 2DG-treated cells the lattice-like structure evident in critical-point-dried cells was condensed into short thick strands that terminated in bulbous ends, whereas in cells recovered for 25 minutes the lattice material was elongated and tapering and the interlattice space relatively expanded. The results obtained support the concept of modulation occurring in the structure of the microtrabecular lattice component of the cytoplasmic ground substance coincident with alterations in cell function and metabolic state.

A study of gluconeogenesis by the administration of 2-deoxyglucose. I

2-Deoxyglucose (2DG) an inhibitor of glucose metabolism, 1 induced hyperglycemia and increased endogenic gluconeogenesis. These effects are seen 5–10 minutes after the administration of 2DG. Two hours later an increased liver glycogen content was found. A rise in ninhydrin-reactive-substances was observed in serum and muscle during the first 20 minutes after 2DG administration. This was followed by a decline. A constant rise in urea excretion was detected beginning 30 minutes after the administration of 2DG. The effect of 2DG was not seen in anesthetized rats. On the other hand, electrical stimulation of the posterior hypothalamus increased gluconeogenesis. 24 The inhibitory effect of sympathetic blocking of this process depends on the nutritional state of the animal. The adrenals were indispensable to the increase of gluconeogenesis. A rise in gluconeogenesis was demonstrated 15 minutes after glucagon administration. The mechanism of acute gluconeogenesis following administration of 2DG is discussed.

Some characteristics of the stimulating effects of 2-deoxy-D-glucose on endogenous fermentation in yeast.

It was shown earlier(1) that 2-deoxy-D-glucose (2DG) elicits a dissimilation of glycogen in yeast, with one mole of CO2 formed for each glucose equivalent of glycogen lost. These data were consistent with a proposed mechanism of cyclic fermentation reported earlier(2) from studies made on dialyzed yeast extracts. In the present paper certain characteristics of the 2DG-stimulated fermentation in cells are presented along with possible implications of such findings.Methods. All experiments were done at 30°C under nitrogen on nonproliferating baker' yeast previously washed and aerated(3). Tris-succinate-tartrate adjusted to appropriate pH served as buffer. CO2 production was measured in a Warburg apparatus. Glycogen was determined using the method of Berke and Rothstein(4) after washing the yeast 3 times with distilled water.Results. Specificity of the stimulatory effect of 2DG; absence of effects of KCl. In Fig. 1 and Table I are shown cumulative CO2 productions by yeast suspensions for various sugars added...

Inhibition of cleavage and development of the sea-urchin egg by 2-desoxy-D-glucose.

Summary2DG inhibits cleavage and oxygen consumption of sea-urchin eggs. High concentrations inhibit cleavage and oxygen uptake at early stages and low concentrations inhibit at later stages of development. The effect of 2DG was counteracted by excess glucose which suggests that 2DG affects cleavage by competitively inhibiting glucose metabolism.