scholarly journals Pentose phosphate pathway activity: effect on in vitro maturation and oxidative status of bovine oocytes

2014 ◽  
Vol 26 (7) ◽  
pp. 931 ◽  
Author(s):  
Cynthia Gutnisky ◽  
Gabriel C. Dalvit ◽  
Jeremy G. Thompson ◽  
Pablo D. Cetica
Keyword(s):  
Glucose Uptake ◽  
Pentose Phosphate Pathway ◽  
Lactate Production ◽  
Pentose Phosphate ◽  
Oxidative Status ◽  
Meiotic Maturation ◽  
Mitochondrial Activity ◽  
Maturation Medium ◽  
Maturation Rate ◽  
Bovine Oocytes

The relationship between pentose phosphate pathway (PPP) activity in cumulus–oocyte complexes (COCs) and oxidative and mitochondrial activity in bovine oocytes was evaluated with the aim of analysing the impact of two inhibitors (NADPH and 6-aminonicotinamide (6-AN)) and a stimulator (NADP) of the key enzymes of the PPP on the maturation rate, oxidative and mitochondrial activity and the mitochondrial distribution in oocytes. The proportion of COCs with measurable PPP activity (assessed using brilliant cresyl blue staining), glucose uptake, lactate production and meiotic maturation rate diminished when 6-AN (0.1, 1, 5 and 10 mM for 22 h) was added to the maturation medium (P < 0.05). The addition of NADPH did not modify glucose uptake or lactate production, but reduced PPP activity in COCs and meiotic maturation rates (P < 0.05). The presence of NADP (0.0125, 0.125, 1.25 and 12.5 mM for 22 h of culture) in the maturation medium had no effect on PPP activity in COCs, glucose uptake, lactate production and meiotic maturation rate. However, in the absence of gonadotropin supplementation, NADP stimulated both glucose uptake and lactate production at 12.5 mM (the highest concentration tested; P < 0.05). NADP did not modify cleavage rate, but decreased blastocyst production (P < 0.05). During IVM, oocyte oxidative and mitochondrial activity was observed to increase at 15 and 22 h maturation, which was also related to progressive mitochondrial migration. Inhibiting the PPP with 6-AN or NADPH led to reduced oxidative and mitochondrial activity compared with the respective control groups and inhibition of mitochondrial migration (P < 0.05). Stimulation of the PPP with NADP increased oxidative and mitochondrial activity at 9 h maturation (P < 0.05) and delayed mitochondrial migration. The present study shows the significance of altering PPP activity during bovine oocyte IVM, revealing that there is a link between the activity of the PPP and the oxidative status of the oocyte.

scholarly journals Glycolytic pathway activity: effect on IVM and oxidative metabolism of bovine oocytes

2013 ◽  
Vol 25 (7) ◽  
pp. 1026 ◽  
Author(s):  
Cynthia Gutnisky ◽  
Sergio Morado ◽  
Gabriel C. Dalvit ◽  
Jeremy G. Thompson ◽  
Pablo D. Cetica
Keyword(s):  
Glucose Uptake ◽  
Central Area ◽  
Lactate Production ◽  
Glycolytic Pathway ◽  
Meiotic Maturation ◽  
Mitochondrial Activity ◽  
Pathway Activity ◽  
Activity Effect ◽  
Maturation Rate ◽  
Pathway Inhibition

The aim of the present study was to determine the effect of altering glycolytic pathway activity during bovine IVM on the meiotic maturation rate, oxidative activity, mitochondrial activity and the mitochondrial distribution within oocytes. Glycolytic activity was manipulated using two inhibitors (ATP, NaF) and a stimulator (AMP) of key enzymes of the pathway. Inhibition of glucose uptake, lactate production and meiotic maturation rates was observed when media were supplemented with ATP or NaF. The addition of AMP to the maturation medium had no effect on glucose uptake, lactate production or meiotic maturation. In the absence of gonadotrophin supplementation, AMP stimulated both glucose uptake and lactate production. However, AMP also decreased cytoplasmic maturation, as determined by early cleavage. During IVM, oocyte oxidative and mitochondrial activity was observed to increase at 15 and 22 h maturation. Inhibiting glycolysis with ATP or NaF led to a reduced oxidative and mitochondrial pattern compared with the respective control groups. Stimulation of the pathway with AMP increased oxidative and mitochondrial activity. A progressive mitochondrial migration to the central area was observed during maturation; oocytes treated with ATP, NaF or AMP showed limited migration. The present study reveals the effects of altering glycolytic pathway activity in cumulus–oocyte complexes, revealing the link between glycolysis of the cumulus–oocyte complex and the oxidative and mitochondrial activity of the oocyte.

scholarly journals 287 INHIBITION OF THE PENTOSE PHOSPHATE PATHWAY RESULTS IN MEIOTIC ARREST IN PORCINE OOCYTES THAT CAN BE OVERCOME BY THE ADDITION OF PATHWAY COFACTORS AND END PRODUCTS

2005 ◽  
Vol 17 (2) ◽  
pp. 293 ◽  
Author(s):  
R. Krisher
Keyword(s):  
Glucose Metabolism ◽  
Pentose Phosphate Pathway ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Pentose Phosphate ◽  
Meiotic Maturation ◽  
Dependent Manner ◽  
Meiotic Arrest ◽  
Immature Oocytes ◽  
Maturation Medium ◽  
End Products

Glucose metabolism is an indicator of oocyte developmental competence, and is also correlated with meiotic maturation. In vitro maturation of porcine oocytes with the pentose phosphate pathway (PPP) inhibitor diphenyleneiodonium (DPI) blocks meiotic progression to metaphase II. The objectives of this study were (1) to examine the reversibility of meiotic arrest induced by DPI; and (2) to overcome metabolically induced meiotic arrest by the addition of PPP end products and cofactors downstream of DPI inhibition. Oocytes were matured for 40 h in standard (defined) maturation media containing 0, 25, 50, or 100 nM DPI. At that time half the oocytes in each treatment (TRT) were fixed, and half were moved into standard maturation medium with no DPI for an additional 40 h, at which time all remaining oocytes were fixed. Two oocytes were matured for 40 h in one of 11 media: standard (defined) maturation medium (STND), standard with 50 nM DPI (DPI), standard with 50 nM DPI and 0.25, 2.5, or 5 mM phosphoribose diphosphate (PRPP), nicotinamide adenine dinucleotide phosphate (NADP), or ribose-5-phosphate (R5P). Additionally, 10 mM R5P and 12.5 mM PRPP were examined. All oocytes were fixed. Oocytes were assigned a meiotic score; germinal vesicle (GV) = 1, GV breakdown (GVBD) = 2, condensed chromatin (CC) = 3, metaphase I (MI) = 4, anaphase (A) = 5, telophase (T) = 6, and metaphase II (MII) = 7. Immature oocytes were classified as those at GV or GVBD stages, and mature oocytes as those at A, T or MII stages. Data were analyzed by ANOVA and are presented as mean ± SEM. After 40 h of arrest (n = 79–87/TRT), increasing concentrations of DPI significantly increased the % of immature oocytes (0, 7.2 ± 2.9; 25, 26.4 ± 4.8; 50, 53.2 ± 5.7; 100, 75.9 ± 4.8) and decreased the % of mature oocytes (0, 73.5 ± 4.9; 25, 52.9 ± 5.4; 50, 20.3 ± 4.6; 100, 0). After an additional 40 hours in standard maturation medium (n = 89–93/TRT), there was no difference in the % of immature oocytes between treatments (0, 7.5 ± 2.8; 25, 14.4 ± 3.7; 50, 13.0 ± 3.5; 100, 9.0 ± 3.0) although the % of mature oocytes significantly decreased with increasing DPI concentration (0, 90.3 ± 3.1; 25, 68.9 ± 4.9; 50, 35.9 ± 5.0; 100, 10.1 ± 3.2). Data from experiment 2 are presented below. Meiotic maturation is significantly inhibited by DPI in a dose-dependent manner. Ability of the oocyte to reach MII following 40 h of arrest is also concentration-dependent, although all treatments resulted in GVBD following removal from DPI. Metabolic arrest can be overcome, resulting in numbers of mature oocytes equal to standard controls, by NADP and PRPP but only moderately by R5P. These data demonstrate that glucose metabolism via the PPP is a critical control mechanism of meiotic maturation in porcine oocytes. Table 1. Effect of PPP cofactors and end products on overcoming metabolically induced meiotic arrest in porcine oocytes

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

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.

Effects of different concentrations of eugenol in maturation medium on bovine oocytes, oxidative status and preimplantation embryos

2021 ◽  
Author(s):  
Lhara Ricarliany Medeiros de Oliveira ◽  
Leonardo Vitorino Costa de Aquino ◽  
Maria Valéria de Oliveira Santos ◽  
Vicente José de Figueirêdo Freitas ◽  
Luciana Medeiros Bertini ◽  
...  
Keyword(s):  
Oxidative Status ◽  
Preimplantation Embryos ◽  
Maturation Medium ◽  
Bovine Oocytes

The effect of serum from obese and normal weight men on glucose metabolism in leucocytes

1980 ◽  
Vol 95 (1) ◽  
pp. 134-138 ◽  
Author(s):  
Ole Myking ◽  
Berit Kjøsen ◽  
Hans H. Bassøe
Keyword(s):  
Glucose Metabolism ◽  
Pentose Phosphate Pathway ◽  
Lactate Production ◽  
Normal Weight ◽  
Pentose Phosphate ◽  
Obese Group ◽  
Stimulation Of

Abstract. The influence of pooled serum from either obese or normal weight males on glucose metabolism in human leucocytes has been studied. Leucocytes from normal weight males were incubated with 10–90% pooled serum and either [U-14C], or [1-14C]glucose. Compared to serum from the normal weight males, serum from the obese group had a more stimulating effect on the 14CO2 and [14C]lactate production from [U-14C]glucose and on the 14CO2 production from [1-14C]glucose. The two serum pools had the same stimulating effect on the Embden-Meyerhof pathway as indicated by the formation of [14C]lactate from [1-14C]glucose. Calculations revealed that the activity in the pentose phosphate pathway was stimulated more by serum from obese, than from normal weight males. It is a possibility that increased stimulation of the pentose phosphate pathway may contribute to the development of overweight.

scholarly journals GLUCOSE METABOLISM OF THE SWIMBLADDER TISSUE OF THE EUROPEAN EEL ANGUILLA ANGUILLA

1993 ◽  
Vol 185 (1) ◽  
pp. 169-178 ◽  
Author(s):  
B. Pelster ◽  
P. Scheid
Keyword(s):  
Glucose Uptake ◽  
Venous Blood ◽  
Lactate Concentration ◽  
Lactate Production ◽  
Anguilla Anguilla ◽  
Pentose Phosphate ◽  
Co2 Production ◽  
European Eel ◽  
O2 Uptake ◽  
Lactate Release

Glucose uptake from, and lactate release into, the blood have been analysed in the active gas- depositing swimbladder of the immobilized European eel Anguilla anguilla. Under normoxic conditions, 0.72 micromole min-1 glucose was removed from the blood supply, while lactate was released into it at a rate of 1.16 micromole min-1. The rate of gas deposition into the swimbladder was significantly correlated with the rate of lactate production. Under hypoxic conditions, glucose consumption by, and lactate production of, the swimbladder tissue were reduced, as was the rate of gas deposition. Compared with normoxic conditions, lactate concentration in the swimbladder tissue was elevated after 1 h of hypoxia, indicating a decrease in lactate release. No difference in the osmolality of arterial and venous blood could be detected in these experiments. Combining the data for glucose uptake and lactate release measured under normoxic conditions with the values for O2 uptake and CO2 production of the swimbladder tissue measured under similar conditions in a previous study, a quantitative evaluation of glucose catabolism was performed. According to the O2 uptake of the tissue, only about 1 % of the glucose was oxidized, while about 80 % was fermented to lactic acid. The remaining 0.14 micromole min-1 glucose was presumably catabolized through the pentose phosphate shunt, as indicated by the CO2 production of 0.16 micromole min-1 that cannot be explained by aerobic metabolism.

161 Dichloroacetate influences the mitochondrial activity of bovine oocytes impairing meiotic progression

2019 ◽  
Vol 31 (1) ◽  
pp. 205
Author(s):  
N. Pagano ◽  
K. Annes ◽  
C. De Canditiis ◽  
J. Ispada ◽  
B. Gasparrini ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pyruvate Dehydrogenase ◽  
Developmental Competence ◽  
Mitochondrial Activity ◽  
Meiotic Progression ◽  
Thermo Fisher Scientific ◽  
Maturation Rate ◽  
Bovine Oocytes ◽  
Fisher Scientific

Pyruvate is a key energy substrate for the oocyte during maturation and acquisition of developmental competence. Mitochondrial activity is also essential for oocyte competence. Dichloroacetate (DCA) is an inhibitor of pyruvate dehydrogenase kinase that indirectly stimulates pyruvate dehydrogenase (PDH), increasing pyruvate oxidation. PDH converts pyruvate into acetyl coenzyme A (acetyl-CoA) and thereby modulates the entry of glucose-derived carbons into the tricarboxylic acid (TCA) cycle, the main ATP production pathway within the oocyte. It was reported that DCA addition to embryo culture media improves embryo development in aged mice, by enhancing mitochondrial membrane potential (MMP) and decreasing oxidative stress (McPherson et al. 2014 Fertil. Steril. 101, 1458-1466). We hypothesised that increased pyruvate metabolism through the oxidative pathway, by stimulating PDH activity with DCA, could influence in vitro oocyte maturation. The aim of this work was to evaluate the effect of different concentrations of DCA during in vitro maturation (IVM) of bovine oocytes on maturation rate and mitochondrial activity, by assessing MMP and levels of flavin adenine dinucleotide (FADH2), nicotinamide adenine dinucleotide hydride (NADH), and reactive oxygen species (ROS). Abattoir-derived bovine cumulus-oocytes complexes (COC; n=360, over 4 replicates) were in vitro-matured with 0 (Control; n=120), 0.5mM (n=120) and 5mM (n=120) of DCA. After maturation, all matured COC were denuded by mechanical pipetting and meiotic progression was assessed by Hoechst 33342 staining and MMP by MitoTracker Red CMXRos test (Thermo Fisher Scientific, Waltham, MA, USA). Moreover, FADH2 and NADH levels were evaluated by autofluorescence (Dumollard et al. Development 134, 455-465) and ROS levels by CellRox® Green test (Thermo Fisher Scientific). Data were analysed by ANOVA, and the Tukey post hoc test was used to evaluate the difference among groups. The α-level was set at 0.05. Treatment with both concentrations of DCA decreased maturation rate (86.1, 67.8, and 67.6% in 0, 0.5, and 5mM groups, respectively; P&lt;0.05). The MMP increased in oocytes matured with the highest concentration of DCA (3.42±0.28, 4.44±0.51, and 6.32±0.89 pixel/mm2, with 0, 0.5, and 5mM DCA, respectively; P&lt;0.05). In line with this, higher levels of FADH2 (3.16±0.15, 3.96±0.24, and 3.83±0.20 pixel/mm2, with 0, 0.5, and 5mM DCA, respectively; P&lt;0.05) and NADH (3.86±0.14, 4.80±0.16, and 4.95±0.17 pixel/mm2, with 0, 0.5, and 5mM DCA, respectively; P&lt;0.05) were found in both DCA-treated groups compared with the control. Unexpectedly, ROS levels increased in the presence of DCA (0.9±0.07, 1.30±0.12, and 1.54±0.16 pixel/mm2, with 0, 0.5, and 5mM DCA, respectively; P&lt;0.05) compared with the control. These results suggest that DCA was effective in stimulating mitochondrial activity of bovine oocytes, but also resulting in increased oxidative stress that likely accounts for the decreased maturation rate. Therefore, alternative strategies should be identified for the manipulation of the oocyte metabolic profile to improve oocyte developmental competence.

167 Effect of Storage Time and Temperature of a Commercial Embryo Holding Medium on the Maturation Kinetics of Immature Bovine Oocytes

2018 ◽  
Vol 30 (1) ◽  
pp. 223
Author(s):  
O. B. Pascottini ◽  
M. Catteeuw ◽  
A. Van Soom ◽  
G. Opsomer
Keyword(s):  
Oocyte Maturation ◽  
Germinal Vesicle ◽  
Holding Time ◽  
Control Group ◽  
Nuclear Maturation ◽  
Maturation Medium ◽  
Maturation Rate ◽  
Maturation Stages ◽  
Bovine Oocytes ◽  
Kinetics Of

The effect of holding time and temperature during storage of immature bovine oocytes in a commercial embryo holding medium (EHM; Syngro® Ltd., Livingston, United Kingdom) was evaluated. Ovaries were collected at the local slaughterhouse and processed within 2 h. Cumulus-oocyte complexes (COC) were collected and allocated to groups of 60. The COC were held in 1-mL sterile glass osmometer tubes, filled to the top with the EHM to limit the amount of air. Vials were capped and covered with parafilm to ensure a tight seal and prevent leakage. Tubes were stored for 6 h at 4°C, room temperature (RT), or 38.5°C; for 10 h at 4°C and RT; and for 14 h at RT. Next, oocytes were fixed after storage in EHM (immature holding) or fixed after being held in EHM and subsequent 22-h maturation at 38.5°C in 5% CO2 in humidified air (mature holding). Maturation medium consisted of modified bicarbonate-buffered TCM-199 supplemented with gentamycin and epidermal growth factor. During all experiments, a control group was included each time. The control consisted of groups of 60 COC immediately fixed after collection or transferred to maturation medium for 22 h and subsequently fixed. Nuclear maturation of oocytes was assessed after Hoechst 33342 staining, using a 400× magnification fluorescence microscope. A total of 3043 COC were evaluated in 3 replicates. Oocytes maturation stages were classified as (1) oocytes in germinal vesicle stage, (2) oocytes in meiotic progression (diakinesis, metaphase I, or anaphase), (3) matured (telophase I or metaphase II), and (4) degenerated (degraded chromatin). Oocytes remained at the germinal vesicle stage when held in EHM (without subsequent maturation) regardless of holding time and temperature (P > 0.05). When oocytes were held for 6 h and subsequently matured (Table 1), the number of matured oocytes was significantly lower for oocytes held at 38.5°C compared with the other groups (control, RT, and 4°C). When held for 10 h, the oocyte maturation rate was similar between the control and RT groups (P > 0.05), but it was significantly lower in oocytes held at 4°C. Last, when compared with oocytes held at RT for 14 h, the maturation rate was higher in the control group (P < 0.05). To conclude, immature bovine oocytes can be successfully held in EHM at RT for up to 10 h. Storing immature oocytes in EHM can delay oocyte maturation and concomitantly synchronize maturation. Table 1.Kinetics of cumulus-oocyte complex nuclear status after storage in embryo holding medium for different times and temperatures and subsequent 22-h maturation

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