scholarly journals Carbohydrate metabolism by murine ovarian follicles and oocytes grown in vitro

Reproduction ◽  
2007 ◽  
Vol 134 (3) ◽  
pp. 415-424 ◽  
Author(s):  
Sarah E Harris ◽  
Iris Adriaens ◽  
Henry J Leese ◽  
Roger G Gosden ◽  
Helen M Picton

Metabolic markers are potentially valuable for assessment of follicle development in vitro. Carbohydrate metabolism of murine preantral follicles grown to maturityover 13 days in vitro has been measured, and metabolism of resulting oocyte–cumulus complexes (OCCs) and denuded oocytes has been compared with in vivo ovulated control counterparts. Spent follicle culture media were analysed for glucose, lactate and pyruvate concentrations. During follicle in vitro growth, glycolysis accounted for a rise from ∼24 to 60% of all glucose consumed. Ovulation induction caused a significant increase in glucose uptake and lactate production by in vitro-grown follicles to 71.7±1.2 and 96.6±4.8 nmoles/day respectively. OCCs grown in vitro had significantly higher rates of glucose consumption and lactate and pyruvate production (110.1± 3.5, 191.8± 8.9 and 31.7± 1.7 pmoles/h respectively) than in vivo ovulated controls (67.4± 8.1, 113.9± 17.1 and 20.2± 4.0 pmoles/h respectively), but a reduced capacity for pyruvate consumption (1.13± 0.06 vs 1.49± 0.06 pmoles/h by in vivo ovulated oocytes). Metabolism of OCCs was affected by the quality of the original follicle. In vitro-grown oocytes had a reduced cytoplasmic volume when compared with controls (168.3± 2.0 vs 199.0± 3.2 proportionately respectively) but a similar rate of metabolism per unit volume. Meiotic status influenced metabolism of both OCCs and denuded oocytes. In conclusion, glucose consumption and lactate production by cultured follicles increased in tandem with developmental progression and were stimulated prior to ovulation. Additionally, the metabolic profiles of in vitro produced OCCs and the oocytes within them are affected by long-term exposure to the culture environment.

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Weixing Dai ◽  
Xianke Meng ◽  
Shaobo Mo ◽  
Wenqiang Xiang ◽  
Ye Xu ◽  
...  

Abstract Background Low expression of FOXE1, a member of Forkhead box (FOX) transcription factor family that plays vital roles in cancers, contributes to poor prognosis of colorectal cancer (CRC) patients. However, the underlying mechanism remains unclear. Materials and methods The effects of FOXE1 on the growth of colon cancer cells and the expression of glycolytic enzymes were investigated in vitro and in vivo. Molecular biological experiments were used to reveal the underlying mechanisms of altered aerobic glycolysis. CRC tissue specimens were used to determine the clinical association of ectopic metabolism caused by dysregulated FOXE1. Results FOXE1 is highly expressed in normal colon tissues compared with cancer tissues and low expression of FOXE1 is significantly associated with poor prognosis of CRC patients. Silencing FOXE1 in CRC cell lines dramatically enhanced cell proliferation and colony formation and promoted glucose consumption and lactate production, while enforced expression of FOXE1 manifested the opposite effects. Mechanistically, FOXE1 bound directly to the promoter region of HK2 and negatively regulated its transcription. Furthermore, the expression of FOXE1 in CRC tissues was negatively correlated with that of HK2. Conclusion FOXE1 functions as a critical tumor suppressor in regulating tumor growth and glycolysis via suppressing HK2 in CRC.


Reproduction ◽  
2005 ◽  
Vol 130 (4) ◽  
pp. 475-483 ◽  
Author(s):  
Kimberly A Preis ◽  
George Seidel ◽  
David K Gardner

In vitro maturation of oocytes has enormous potential in assisted reproductive technology, but its use has been limited due to insufficient knowledge of oocyte physiology during this dynamic period and lack of an adequate maturation system. The aim of this study was to characterize the metabolic profiles of three groups of oocytes throughout maturation: cumulus–oocyte complexes (COCs), denuded oocytes, and denuded oocytes co-cultured with cumulus cells. Mouse oocytes were collected from 28-day-old unstimulated females and matured in a defined medium. Oocytes were matured individually and transferred into fresh 0.5 μl drops of medium at 4 h intervals until 16 h. Ultramicrofluorimetry was used to quantitate carbohydrate consumption from and metabolite release into the medium. Glucose consumption and lactate production of COCs increased (P < 0.001) over the maturation interval (0–16 h). Glucose consumption by COCs that subsequently fertilized was higher between 8–12 h of maturation than by COCs that did not fertilize (38 versus 29 pmol/COC per h, respectively; P < 0.01). Lactate production by COCs that subsequently fertilized was higher between 8–16 h of maturation, than by oocytes that did not fertilize (8–12 h, 66 versus 46 pmol/COC per h, P < 0.01; 12–16 h, 56 versus 40 pmol/COC per h, respectively; P < 0.05). These data indicate that the final hours of maturation may hold a unique marker of oocyte competence, as during this time fertilizable COCs take up more glucose and produce more lactate than those not subsequently fertilized.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e15123-e15123
Author(s):  
Dawei Li ◽  
Qingguo Li ◽  
Sanjun Cai ◽  
Keping Xie

e15123 Background: Aberrant expression of Forkhead Box transcription factors plays vital roles in the oncogenesis and metastasis of many types of cancer. The purpose of this study is to elucidate the function of Forkhead Box C1(FOXC1) in colorectal cancer (CRC)malignancy maintenance. Methods: FOXC1 expression in CRC specimens was analyzed in the TCGA database and validated by immunohistochemistry using a tissue microarray (TMA). The effect of FOXC1 expression on cancer proliferation and glycolysis was assessed in cells by altering the expression of FOXC1 in vitro and in vivo. Mechanistic investigation was carried out by using cell and molecular biology approaches. Results: FOXC1 was found to be overexpressed in CRC specimens compared with that in the adjacent benign tissues. Univariate survival analyses of the TCGA and validated cohorts showed that high expression of FOXC1 was significantly correlated with shortened patient survival ( P< 0.05). Attenuation of FOXC1 expression inhibited proliferation, clone formation and decreased glucose consumption and lactate production. By contrast, overexpression of FOXC1 had the opposite effect. Furthermore, increased FOXC1 expression downregulated the expression of a key glycolytic enzyme,fructose-1, 6-Bisphosphatase 1 (FBP1). Mechanistically, FOXC1 bound directly to the promoter regions of the FBP1 gene and negatively regulated its transcriptional activity. Aberrant FBP1 expression contributes to CRC tumorigenicity, and decreased FBP1 coupled with increased FOXC1 provided better prognostic information than FOXC1 did alone. Conclusions: The FOXC1/FBP1 axis induces cell proliferation, reprograms the metabolic process in CRC and provides potential prognostic predictors and therapeutic targets for patients with CRC.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Linfei Huang ◽  
Lei Zhu ◽  
Sheng Pan ◽  
Jing Xu ◽  
Miao Xie ◽  
...  

Abstract Background Circular RNA 0029803 (circ_0029803) was found to be upregulated in colorectal cancer (CRC) tissues, but its function and underlying molecular mechanism are not studied in CRC. Methods The expression levels of circ_0029803, microRNA-216b-5p (miR-216b-5p), and ski-oncogene-like (SKIL) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). RNase R treatment was used to affirm the existence of circ_0029803. Cell proliferation, apoptosis, migration, and invasion were assessed by colony formation, flow cytometry, and Transwell assays, respectively. A glucose and lactate assay kit was used to detect glucose consumption and lactate production. Western blot was applied to analyze the levels of all proteins. Dual-luciferase reporter assay was performed to assess the relationship between miR-216b-5p and circ_0029803 or SKIL. Tumor xenograft models were established to elucidate the effect of circ_0029803 in vivo. Results Circ_0029803 expression was enhanced in CRC tissues and cells, and the 5-year overall survival rate of patients with high circ_0029803 expression was substantially reduced. Circ_0029803 depletion retarded proliferation, migration, invasion, EMT and glycolysis of CRC cells in vitro as well as the tumor growth in vivo. Mechanically, circ_0029803 could serve as miR-216b-5p sponge to regulate its expression, and miR-216b-5p knockdown reversed the inhibition of si-circ_0029803 on the malignant behaviors of CRC cells. Additionally, as the target mRNA of miR-216b-5p, SKIL could counteract the inhibitory effect of miR-216b-5p on the development of CRC cells. Importantly, silencing circ_0029803 reduced SKIL expression via sponging miR-216b-5p. Conclusion Circ_0029803 knockdown hindered proliferation, migration, invasion, EMT, and glycolysis and promoted apoptosis in CRC cells by modulating the miR-216b-5p/SKIL axis.


1991 ◽  
Vol 275 (2) ◽  
pp. 477-483 ◽  
Author(s):  
P A MacLennan ◽  
A McArdle ◽  
R H Edwards

1. mdx mice do not express dystrophin, the product of the gene which is defective in Duchenne and Becker muscular dystrophy. We have previously shown that protein-synthetic rates (ks) are increased in mdx mouse muscles [MacLennan & Edwards (1990) Biochem. J. 268, 795-797]. 2. The tumour-promoting stereoisomer of phorbol 12,13-didecanoate (4 beta-PDD) acutely increased the ks of muscles from mdx and wild-type (C57BL/10) mice incubated in vitro in the absence of insulin. The effects of 4 beta-PDD are presumably mediated by activation of protein kinase C (PKC). 3. The muscle glycogen concentrations of mdx mice were higher than those of C57BL/10 mice. Studies performed in vivo and in vitro suggested that the effect might be at least partially due to increased rate of glycogen synthesis in mdx muscle. 4. 4 beta-PDD increased the glycogen-synthetic rates rates of C57BL/10, but not mdx, muscles incubated in vitro in the absence of insulin. 5. In muscles from both species incubated in the absence of insulin, treatment with 4 beta-PDD also induced increased rates of glucose uptake and lactate production. Kinetic studies of C57BL/10 and mdx muscles suggested that 4 beta-PDD raised the Vmax. of glucose uptake, but did not alter the Km for the process. 6. The possible role of PKC in controlling the protein and carbohydrate metabolism of normal and mdx mouse muscles is discussed.


2020 ◽  
Vol 40 (6) ◽  
Author(s):  
Xinhui Fang ◽  
Yangqiu Bai ◽  
Lida Zhang ◽  
Songze Ding

Abstract Background: Gastric cancer (GC) is a malignant tumor of the digestive tract. Hypoxia plays an important role in the development of cancer, including GC. The present study aimed to investigate the role of circular RNA SLAMF6 (circSLAMF6) in the progression of GC under hypoxia. Methods: The expression of circSLAMF6, microRNA-204-5p (miR-204-5p) and myosin heavy chain 9 (MYH9) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). GC cells were maintained under hypoxia (1% O2) for experiments in vitro. Glucose consumption and lactate production were determined by a Glucose Assay Kit and a Lactate Assay Kit, respectively. Levels of all protein were detected by Western blot. Cell migration and invasion were examined by Transwell assay. The interaction between miR-204-5p and circSLAMF6 or MYH9 was analyzed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Murine xenograft model was established to explore the role of circSLAMF6 in vivo. Results: CircSLAMF6 expression was increased in GC cells under hypoxia. Hypoxia promoted glycolysis, migration, and invasion in GC cells, which were reversed by circSLAMF6 knockdown. CircSLAMF6 was validated as a miR-204-5p sponge, and MYH9 was a target of miR-204-5p. Functionally, miR-204-5p inhibitor weakened the inhibition of circSLAMF6 knockdown on GC cell progression under hypoxia. Besides, MYH9 depletion suppressed glycolysis, migration, and invasion in GC cells under hypoxia. Importantly, circSLAMF6 deficiency inhibited tumor growth in vivo by regulating the miR-204-5p/MYH9 axis. Conclusion: CircSLAMF6 was involved in glycolysis, migration, and invasion by regulating the miR-204-5p/MYH9 axis in GC cells under hypoxia.


2015 ◽  
Vol 112 (35) ◽  
pp. 11090-11095 ◽  
Author(s):  
Rodrigo Lerchundi ◽  
Ignacio Fernández-Moncada ◽  
Yasna Contreras-Baeza ◽  
Tamara Sotelo-Hitschfeld ◽  
Philipp Mächler ◽  
...  

Neural activity is accompanied by a transient mismatch between local glucose and oxygen metabolism, a phenomenon of physiological and pathophysiological importance termed aerobic glycolysis. Previous studies have proposed glutamate and K+ as the neuronal signals that trigger aerobic glycolysis in astrocytes. Here we used a panel of genetically encoded FRET sensors in vitro and in vivo to investigate the participation of NH4+, a by-product of catabolism that is also released by active neurons. Astrocytes in mixed cortical cultures responded to physiological levels of NH4+ with an acute rise in cytosolic lactate followed by lactate release into the extracellular space, as detected by a lactate-sniffer. An acute increase in astrocytic lactate was also observed in acute hippocampal slices exposed to NH4+ and in the somatosensory cortex of anesthetized mice in response to i.v. NH4+. Unexpectedly, NH4+ had no effect on astrocytic glucose consumption. Parallel measurements showed simultaneous cytosolic pyruvate accumulation and NADH depletion, suggesting the involvement of mitochondria. An inhibitor-stop technique confirmed a strong inhibition of mitochondrial pyruvate uptake that can be explained by mitochondrial matrix acidification. These results show that physiological NH4+ diverts the flux of pyruvate from mitochondria to lactate production and release. Considering that NH4+ is produced stoichiometrically with glutamate during excitatory neurotransmission, we propose that NH4+ behaves as an intercellular signal and that pyruvate shunting contributes to aerobic lactate production by astrocytes.


2001 ◽  
Vol 2001 ◽  
pp. 216-216
Author(s):  
N.M. Orsi ◽  
J.B. Reischl ◽  
H.J. Leese

In vitro-produced (IVP) bovine embryos are used in a wide range of biotechnologies but develop less well than their in vivo counterparts and can give rise to foetal/neonatal anomalies after embryo transfer. The quality of bovine IVP embryos and the systems in which they are produced are traditionally assessed in terms of morphological and developmental criteria; namely, embryo grade and blastocyst formation rate. Lane and Gardner (1996) showed that mouse embryos selected for transfer on the basis of a low glycolytic activity (conversion of glucose to lactate), measured non-invasively, were 4 times more likely to implant than those selected randomly. Comparable data are not available for bovine embryos. The aim of this study was to assess linear glycolytic index of cattle blastocysts in vitro as a marker of viability. We have measured glucose consumption and lactate production by individual bovine IVP embryos grown in cell-free conditions and in a novel co-culture system (Orsi et al., 2000) involving confluent bovine oviduct epithelial cell monolayers on permeable supports. This preparation allows the epithelial cells to be fed by a nutritionally-rich medium via the physiological, basal, route, while the apical medium, containing the embryos, is more dilute, mimicking oviduct fluid.


1966 ◽  
Vol 51 (2) ◽  
pp. 193-202
Author(s):  
J. A. Antonioli ◽  
A. Vannotti

ABSTRACT 1. The metabolism of suspensions of circulating leucocytes has been studied after intramuscular injection of a dose of 50 mg/kg of a corticosteroid (cortisone acetate). The suspensions were incubated under aerobic conditions in the presence of a glucose concentration of 5.6 mm. Glucose consumption, lactate production, and variations in intracellular glycogen concentration were measured. After the administration of the corticosteroid, the anabolic processes of granulocyte metabolism were reversibly stimulated. Glucose consumption and lactate production increased 12 hours after the injection, but tended to normalize after 24 hours. The glycogen content of the granulocytes was enhanced, and glycogen synthesis during the course of the incubation was greatly stimulated. The action of the administered corticosteroid is more prolonged in females than in males. The injection of the corticosteroid caused metabolic modifications which resemble in their modulations and in their chronological development those found in circulating granulocytes of guinea-pigs suffering from sterile peritonitis. These results suggest, therefore, that, in the case of acute inflammation, the glucocorticosteroids may play an important role in the regulation of the metabolism of the blood leucocytes.


Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 60
Author(s):  
Juan Vélez ◽  
Zahady Velasquez ◽  
Liliana M. R. Silva ◽  
Ulrich Gärtner ◽  
Klaus Failing ◽  
...  

Cryptosporidium parvum is an apicomplexan zoonotic parasite recognized as the second leading-cause of diarrhoea-induced mortality in children. In contrast to other apicomplexans, C.parvum has minimalistic metabolic capacities which are almost exclusively based on glycolysis. Consequently, C. parvum is highly dependent on its host cell metabolism. In vivo (within the intestine) infected epithelial host cells are typically exposed to low oxygen pressure (1–11% O2, termed physioxia). Here, we comparatively analyzed the metabolic signatures of C. parvum-infected HCT-8 cells cultured under both, hyperoxia (21% O2), representing the standard oxygen condition used in most experimental settings, and physioxia (5% O2), to be closer to the in vivo situation. The most pronounced effect of C. parvum infection on host cell metabolism was, on one side, an increase in glucose and glutamine uptake, and on the other side, an increase in lactate release. When cultured in a glutamine-deficient medium, C. parvum infection led to a massive increase in glucose consumption and lactate production. Together, these results point to the important role of both glycolysis and glutaminolysis during C. parvum intracellular replication. Referring to obtained metabolic signatures, we targeted glycolysis as well as glutaminolysis in C. parvum-infected host cells by using the inhibitors lonidamine [inhibitor of hexokinase, mitochondrial carrier protein (MCP) and monocarboxylate transporters (MCT) 1, 2, 4], galloflavin (lactate dehydrogenase inhibitor), syrosingopine (MCT1- and MCT4 inhibitor) and compound 968 (glutaminase inhibitor) under hyperoxic and physioxic conditions. In line with metabolic signatures, all inhibitors significantly reduced parasite replication under both oxygen conditions, thereby proving both energy-related metabolic pathways, glycolysis and glutaminolysis, but also lactate export mechanisms via MCTs as pivotal for C. parvum under in vivo physioxic conditions of mammals.


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