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 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 Chronically increased glucose uptake by adipose tissue leads to lactate production and improved insulin sensitivity rather than obesity in the mouse

Diabetologia ◽  
2010 ◽  
Vol 53 (11) ◽  
pp. 2417-2430 ◽  
Author(s):  
S. Muñoz ◽  
S. Franckhauser ◽  
I. Elias ◽  
T. Ferré ◽  
A. Hidalgo ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Insulin Sensitivity ◽  
Glucose Uptake ◽  
Lactate Production

scholarly journals α-Hederin Inhibits the Growth of Lung Cancer A549 Cells in vitro and in vivo by Increasing SIRT6 Dependent Glycolysis

2020 ◽  
Author(s):  
cong fang ◽  
Yahui Liu ◽  
Lanying Chen ◽  
Yingying Luo ◽  
Yaru Cui ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Mouse Model ◽  
Protein Expression ◽  
Glucose Uptake ◽  
A549 Cells ◽  
Lactate Production ◽  
Tumor Xenograft ◽  
Xenograft Mouse Model ◽  
Atp Generation

Abstract Background: α-hederin an effective component of Pulsatilla chinensis (Bunge) Regel, Studies showed that α-hederin exert many pharmacological activities, However, the effect of α-hederin on metabolism is still unclear. This study aimed to illuminate the role of α-hederin in glucose metabolism in lung cancer cells and investigate the molecular mechanism of α-hederin. Methods: CCK8 and colony formation assays were employed to assess the anti-proliferative effects induced by α-hederin. Glucose uptake, ATP generation, and reduced lactate production were measured using kits, and an A549 tumor xenograft mouse model of lung cancer was used to assess the in vivo antitumor effect of α-hederin (5, 10 mg/kg). Glycolytic-related key enzymes hexokinase 2 (HK2), glucose transporters 1 (GLUT1), pyruvate kinase M2 (PKM2), lactate dehydrogenase A (LDHA), monocarboxylate transporter (MCT4), c-Myc, Hypoxia inducible factor-1α (HIF-1α) and Sirtuin 6 (SIRT6) protein expression were detected by western blotting and immunohistochemical staining and SIRT6 inhibitors was verified in A549 cells. Results: Our results showed that cell proliferation was significantly inhibited by α-hederin in a dose-dependent manner and that α-hederin inhibited glucose uptake and ATP generation and reduced lactate production. Furthermore, α-hederin remarkably inhibited HK2, GLUT1, PKM2, LDHA, MCT4, c-Myc, HIF-1α and activated SIRT6 protein expression. Using inhibitors, we proved that α-hederin inhibits glycolysis by activating SIRT6. Moreover, a tumor xenograft mouse model of lung cancer further confirmed that α-hederin inhibits lung cancer growth via inhibiting glycolysis in vivo. Conclusions: α-hederin inhibits the growth of non-small cell lung cancer A549 cells by inhibiting glycolysis. The mechanism of glycolysis inhibition includes α-hederin activating the expression of the glycolytic related protein SIRT6.

scholarly journals Human TNF-α Affects the Egg-laying Dynamics and Glucose Metabolism of Schistosoma Mansoni Adult Worms in Vitro

2021 ◽  
Author(s):  
Ednilson Hilário Lopes-Junior ◽  
Gilbert de Oliveira Silveira ◽  
Camila Banca Guedes ◽  
Gratchela Dutra Rodrigues ◽  
Viviane Sousa Ribeiro ◽  
...  
Keyword(s):  
Schistosoma Mansoni ◽  
Mrna Expression ◽  
Glucose Uptake ◽  
Lactate Production ◽  
Egg Laying ◽  
Dependent Manner ◽  
Tnf Α ◽  
Atp Metabolism ◽  
Fine Regulation

Abstract Several studies described the effect of human TNF-α on Schistosoma mansoni. It affects the worm’s development, metabolism, egg-laying, changes in the parasite´s gene expression and protein phosphorylation. Data available concerning the influence of hTNF-α on egg-laying are controversial and understanding the mechanism of egg-laying regulation is essential in combating schistosomiasis. We characterized the effects of in vitro treatment of S. mansoni adult worms with different doses of hTNF-α (5, 20 and 40ng/mL) for five days. We explored the effects on the egg-laying rate, glucose, ATP metabolism, mRNA expression levels of lactate dehydrogenase, of glucose transporters and of SmTNFR, the parasite gene for hTNF-α receptor. hTNF-α influenced egg-laying in a time and dose dependent manner: with 40ng/mL, egg-laying increased on day 2 and decreased on days 3 and 4; 20 ng/mL dose, egg-laying decreased on day 3, while at 5ng/mL dose, egg-laying decreased on day 4. The total number of eggs produced was not affected, but the egg-laying dynamic was altered; the median egg-laying time decreased significantly due to treatment. At 5 and 20ng/mL hTNF-alpha, lactate production diminished on days 3 up to 5, while glucose uptake increased on day 5. At 40ng/mL, glucose uptake diminished on days 1 up to 3, while ATP accumulation was detected on day 5. No significant changes in the mRNA expression were detected in all treatments. Crosstalk involving the hTNF-alpha and the parasite signaling play a role in the fine regulation of the worm´s metabolism and physiology and points to new strategies for disease control.

scholarly journals Central metabolism of functionally heterogeneous mesenchymal stromal cells

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mario Barilani ◽  
Roberta Palorini ◽  
Giuseppina Votta ◽  
Roberta Piras ◽  
Giuseppe Buono ◽  
...  
Keyword(s):  
Stem Cells ◽  
Oxidative Phosphorylation ◽  
Cell Fate ◽  
Lactate Production ◽  
Glucose Consumption ◽  
Mitochondrial Activity ◽  
Central Metabolism ◽  
Mt Dna ◽  
Differentiation Potential ◽  
And Function

Abstract Metabolism and mitochondrial biology have gained a prominent role as determinants of stem cell fate and function. In the context of regenerative medicine, innovative parameters predictive of therapeutic efficacy could be drawn from the association of metabolic or mitochondrial parameters to different degrees of stemness and differentiation potentials. Herein, this possibility was addressed in human mesenchymal stromal/stem cells (hMSC) previously shown to differ in lifespan and telomere length. First, these hMSC were shown to possess significantly distinct proliferation rate, senescence status and differentiation capacity. More potential hMSC were associated to higher mitochondrial (mt) DNA copy number and lower mtDNA methylation. In addition, they showed higher expression levels of oxidative phosphorylation subunits. Consistently, they exhibited higher coupled oxygen consumption rate and lower transcription of glycolysis-related genes, glucose consumption and lactate production. All these data pointed at oxidative phosphorylation-based central metabolism as a feature of higher stemness-associated hMSC phenotypes. Consistently, reduction of mitochondrial activity by complex I and III inhibitors in higher stemness-associated hMSC triggered senescence. Finally, functionally higher stemness-associated hMSC showed metabolic plasticity when challenged by glucose or glutamine shortage, which mimic bioenergetics switches that hMSC must undergo after transplantation or during self-renewal and differentiation. Altogether, these results hint at metabolic and mitochondrial parameters that could be implemented to identify stem cells endowed with superior growth and differentiation potential.

Effects of insulin on glucose uptake by rat hearts during and after coronary flow reduction

1997 ◽  
Vol 273 (5) ◽  
pp. H2170-H2177 ◽  
Author(s):  
T. Minsue Chen ◽  
Gary W. Goodwin ◽  
Patrick H. Guthrie ◽  
Heinrich Taegtmeyer
Keyword(s):  
Glucose Uptake ◽  
Intracellular Signaling ◽  
Glycogen Synthesis ◽  
Lactate Production ◽  
Low Flow ◽  
Rat Hearts ◽  
Ischemic Period ◽  
Postischemic Period ◽  
Insulin Responsiveness ◽  
Fasted Rats

We tested the hypothesis that low-flow ischemia increases glucose uptake and reduces insulin responsiveness. Working hearts from fasted rats were perfused with buffer containing glucose alone or glucose plus a second substrate (lactate, octanoate, or β-hydroxybutyrate). Rates of glucose uptake were measured by3H2O production from [2-3H]glucose. After 15 min of perfusion at a physiological workload, hearts were subjected to low-flow ischemia for 45 min, after which they were returned to control conditions for another 30 min. Insulin (1 mU/ml) was added before, during, or after the ischemic period. Cardiac power decreased by 70% with ischemia and returned to preischemic values on reperfusion in all groups. Low-flow ischemia increased lactate production, but the rate of glucose uptake during ischemia increased only when a second substrate was present. Hearts remained insulin responsive under all conditions. Insulin doubled glucose uptake when added under control conditions, during low-flow ischemia, and at the onset of the postischemic period. Insulin also increased net glycogen synthesis in postischemic hearts perfused with glucose and a second substrate. Thus insulin stimulates glucose uptake in normal and ischemic hearts of fasted rats, whereas ischemia stimulates glucose uptake only in the presence of a cosubstrate. The results are consistent with two separate intracellular signaling pathways for hexose transport, one that is sensitive to the metabolic requirements of the heart and another that is sensitive to insulin.

scholarly journals Evidence for a negative Pasteur effect in articular cartilage

1997 ◽  
Vol 321 (1) ◽  
pp. 95-102 ◽  
Author(s):  
Robert B. LEE ◽  
Jill P. G. URBAN
Keyword(s):  
Articular Cartilage ◽  
Glucose Uptake ◽  
Lactate Production ◽  
Pasteur Effect ◽  
Anoxic Conditions ◽  
Atp Production ◽  
Bovine Articular Cartilage ◽  
Atp Concentration ◽  
O2 Concentration ◽  
Lactate Formation

Uptake of external glucose and production of lactate were measured in freshly-excised bovine articular cartilage under O2 concentrations ranging from 21% (air) to zero (N2-bubbled). Anoxia (O2 concentration < 1% in the gas phase) severely inhibited both glucose uptake and lactate production. The decrease in lactate formation correlated closely with the decrease in glucose uptake, in a mole ratio of 2:1. This reduction in the rate of glycolysis in anoxic conditions is seen as evidence of a negative Pasteur effect in bovine articular cartilage. Anoxia also suppressed glycolysis in articular cartilage from horse, pig and sheep. Inhibitors acting on the glycolytic pathway (2-deoxy-d-glucose, iodoacetamide or fluoride) strongly decreased aerobic lactate production and ATP concentration, consistent with the belief that articular cartilage obtains its principal supply of ATP from substrate-level phosphorylation in glycolysis. Azide or cyanide lowered the ATP concentration in aerobic cartilage to approximately the same extent as did anoxia but, because glycolysis (lactate production) was also inhibited by these treatments, the importance of any mitochondrial ATP production could not be assessed. A negative Pasteur effect would make chondrocytes particularly liable to suffer a shortage of energy under anoxic conditions. Incorporation of [35S]sulphate into proteoglycan was severely curtailed by treatments, such as anoxia, which decreased the intracellular concentration of ATP.

341 OXYGEN TENSION AND EGF AFFECT METABOLISM OF IN VITRO-MATURED CUMULUS-ENCLOSED MOUSE OOCYTES

2006 ◽  
Vol 18 (2) ◽  
pp. 278
Author(s):  
K. A. Preis ◽  
G. E. Seidel Jr ◽  
D. K. Gardner
Keyword(s):  
Glucose Uptake ◽  
Oxygen Tension ◽  
Embryo Development ◽  
Metabolic Activity ◽  
Lactate Production ◽  
Defined Medium ◽  
Blastocyst Development ◽  
Developmental Potential ◽  
Exact Test

In vitro maturation of immature oocytes results in limited success in both clinical and research laboratories. Although reduced oxygen concentration is beneficial to embryo development, the optimal concentration for oocyte maturation has yet to be determined. The objective of this study was to determine whether oxygen tension (20% or 5% O2) affects oocyte physiology. Additionally, the effect of epidermal growth factor (EGF) in maturation medium on oocyte metabolic activity and subsequent embryo development was determined. Cumulus–oocyte complexes (COCs; n = 231) were collected from 28-day-old unprimed F1 (C57BL/6 × CBA/ca) mice. COCs were individually matured in defined medium at 37°C in 6% CO2 in one of four groups (Table 1). For the metabolism study, COCs were further divided into two groups: individual maturation in a 2-µL drop of medium for 16 h (n = 131); or individual maturation in 5-μL for 12 h and then placed in a 0.5-μL drop of medium for 4 h (n = 100), the time of greatest metabolic activity of the COC. At 17 h of maturation, COCs were individually fertilized, and zygotes were individually cultured until 96 h, at which time blastocyst development was assessed. Metabolic profiles were analyzed by ANOVA, and blastocyst rates were analyzed by Fisher's exact test. Maturation rates and blastocyst development were not different between groups. However, at 12–16 h of maturation, metabolism of COCs was affected by both oxygen tension and EGF (Table 1). Concerning metabolism over the entire course of maturation, glucose uptake and lactate production were higher in COCs in 5% O2 + 100 ng EGF (P < 0.05) than in the remaining three groups. There was no difference between 5% O2 and 20% O2 + 100 ng EGF, but 20% O2 caused less glucose uptake and lactate production than did the other three treatment groups (P < 0.05). Results of this study are the first to show that oxygen tension alters COC metabolism: COCs matured under 5% O2 were more active metabolically than COCs matured under 20% O2. The effect of oxygen tension is to some extent moderated by the presence of EGF, as metabolic activity of COCs matured under 20% O2 + 100 ng EGF was closer to that of COCs matured under 5% O2 conditions. Although blastocyst rates were similar across the four groups, embryos derived from oocytes matured in different oxygen tensions may exhibit different developmental potential. In conclusion, results of this study have implications for the improvement of maturation conditions in both clinical and research laboratories. Table 1. Carbohydrate metabolism of individual COCs at 12–16 h of maturation

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