scholarly journals Cumulus expansion and glucose utilisation by bovine cumulus–oocyte complexes during in vitro maturation: the influence of glucosamine and follicle-stimulating hormone

Reproduction ◽  
2004 ◽  
Vol 128 (3) ◽  
pp. 313-319 ◽  
Author(s):  
Melanie L Sutton-McDowall ◽  
Robert B Gilchrist ◽  
Jeremy G Thompson

Glucose is an important metabolite and its presence during in vitro oocyte maturation (IVM) can have profound effects on the oocyte’s developmental capacity. We have demonstrated that glucose uptake increases over a 24 h IVM period, with most accounted for as l-lactate production. However, as maturation proceeds, l-lactate production remains constant, suggesting an alternative role for glucose metabolism. We hypothesised that in the latter stages of oocyte maturation, glucose not accounted for by l-lactate production is utilised for FSH-stimulated extracellular matrix (ECM) synthesis. To examine precursor utilisation for synthesis of ECM, bovine cumulus–oocyte complexes (COCs) were matured in ± FSH and/or glucosamine (an alternative substrate of matrix components). Measurements included COC diameters, glucose consumption and l-lactate production in spent media and [U-14C]glucose incorporation into ECM. FSH significantly stimulated both diameter and glucose consumption during 20–24 h maturation compared with unstimulated complexes, although co-incubation with glucosamine and FSH decreased total glucose consumption 1.7-fold compared with FSH alone (P < 0.05). Furthermore, there was a linear relationship between glucose and l-lactate metabolism in the presence of glucosamine, suggesting that the majority of glucose was being utilised for l-lactate production via glycolysis. In the presence of glucosamine, twofold less [U-14C]glucose was incorporated into matrix compared with COCs cultured without glucosamine. These results support the hypothesis that there is a link between glucose and glucosamine uptake in FSH-stimulated ECM synthesis. Furthermore, glucose has multiple fates within the COC during maturation and levels of utilisation are dependent on the composition of the maturation environment.

Reproduction ◽  
2003 ◽  
pp. 197-204 ◽  
Author(s):  
RG Sturmey ◽  
HJ Leese

Pig oocytes and embryos differ from those of other species in having a large quantity of endogenous lipid, a potential role for which has yet to be identified. In the present study, the hypothesis that endogenous triglyceride acts as a metabolic substrate during in vitro maturation and early embryo development was tested. Embryos were produced by in vitro fertilization (IVF) of in vitro-matured, abattoir-derived immature oocytes, cultured in medium NCSU23 up to the blastocyst stage. The triglyceride content of single oocytes and embryos was measured throughout development. Oxygen and glucose consumption and the formation of lactate were measured non-invasively over the same period, enabling total ATP production to be calculated. The triglyceride content of oocytes before maturation (135+/-4.9 ng) decreased by 13 ng (P<0.05) during in vitro maturation, but there was no apparent change in triglyceride content during embryo development (117.68 ng). Oxygen consumption was low throughout embryo cleavage before reaching a peak at the blastocyst stage (P<0.01), a pattern similar to that seen in other mammals studied. Glucose consumption and lactate production were also at a maximum at the blastocyst stage (P<0.05). These data indicate that pig oocytes may use endogenous triglyceride as an energy source during in vitro maturation and that most (91-97%) of the ATP produced during embryo development comes from oxidative phosphorylation. The high exogenous glucose concentration in NCSU23 (5.5 mmol l(-1)) may be needed to form pyruvate, which in turn, produces oxaloacetate, which is required to prime the tricarboxylic acid cycle. However, the reason for the high lipid content in early pig embryos remains to be elucidated.


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.


Zygote ◽  
2021 ◽  
pp. 1-7
Author(s):  
Luciana Diniz Rola ◽  
Eveline dos Santos Zanetti ◽  
Maite del Collado ◽  
Ellen de Fátima Carvalho Peroni ◽  
José Maurício Barbanti Duarte

Summary In vitro production of embryos has gained prominence as a tool for use in wildlife conservation programmes in situ and ex situ. However, the development of this technique depends on steps that include ovarian stimulation, collection and oocyte maturation. The purpose of this study was to assess the feasibility of an ovarian stimulation protocol for follicular aspiration, the efficiency of videolaparoscopy for follicular aspiration and test a medium for in vitro oocyte maturation for the species Mazama gouazoubira. Five females were submitted to repeated ovarian stimulation (hormone protocol using controlled internal drug release), and estradiol benzoate on D0 and eight injections of follicle-stimulating hormone, once every 12 h, from D4 onwards at 30-day intervals. Fourteen surgical procedures were performed in superstimulated females, resulting in the collection of 94 oocytes and an average of 17.1 ± 9.1 follicles observed, 13.5 ± 6.6 follicles aspirated and 7.2 ± 3.7 oocytes collected per surgery. After collection, the oocytes were submitted to in vitro maturation for 24 h and stained with Hoechst 33342 dye to evaluate their nuclear status; 64.5% of the oocytes reached MII and 16.1% were spontaneously activated by parthenogenesis. The nuclear status of oocytes that did not undergo in vitro maturation was evaluated; 80.9% were found to be immature.


2021 ◽  
Vol 10 (13) ◽  
pp. 2757
Author(s):  
Xia Hao ◽  
Amandine Anastácio ◽  
Kenny A. Rodriguez-Wallberg

Fertility preservation through ovarian stimulation, aiming at cryopreserving mature oocytes or embryos, is sometimes unsuccessful. This clinical situation deserves novel approaches to overcome infertility following cancer treatment in patients facing highly gonadotoxic treatment. In this controlled experimental study, we investigated the feasibility of in-vitro culturing secondary follicles isolated from superovulated ovaries of mice recently treated with gonadotropins. The follicle yields of superovulated ovaries were 45.9% less than in unstimulated controls. Follicles from superovulated ovaries showed faster growth pace during the initial 7 days of culture and secreted more 17β-estradiol by the end of culture vs controls. Parameters reflecting the outcome of follicular development and oocyte maturation competence in vitro were similar between superovulated and control groups, with a similar follicle size at the end of culture and around 70% survival. Nearly half of cultured follicles met the criteria for in-vitro maturation in both groups and approximately 60% of those achieved a mature MII oocyte, similarly in both groups. Over 60% of obtained MII oocytes displayed normal-looking spindle and chromosome configurations, without significant differences between the groups. Using a validated follicle culture system, we demonstrated the feasibility of secondary follicle isolation, in-vitro culture and oocyte maturation with normal spindle and chromosome configurations obtained from superovulated mice ovaries.


1975 ◽  
Vol 49 (5) ◽  
pp. 375-384
Author(s):  
N. Worathumrong ◽  
A. J. Grimes

1. Some effects of sodium salicylate upon anaerobic glycolysis have been studied in normal human erythrocytes incubated for up to 6 h at 37°C in autologous sera. 2. Both glucose consumption and lactate production were stimulated by concentrations of salicylate up to 60 mmol/l but at the highest concentration used (90 mmol/l) an initial stimulus was followed by inhibition of glycolysis. 3. Losses occurred of adenosine 5′-triphosphate (ATP), adenosine 5′-diphosphate (ADP) and adenosine 5′-phosphate (AMP) at higher concentrations of salicylate and there was a concomitant increase of inorganic phosphate. 4. Other phosphate esters underwent concentration changes at higher concentrations of salicylate that reflected inadequate concentrations of ATP for glycolysis. 5. The rates of sodium efflux from, and potassium influx into, erythrocytes were unaffected by the presence of salicylate at concentrations sufficient to stimulate glycolysis.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
I Viran. . Klun ◽  
J Bedenk ◽  
N Jancar

Abstract Study question Do different types of cancer affect the success of oocyte maturation in vitro compared to infertile women included in the in vitro fertilization (IVF) program? Summary answer Cancer does not adversely affect oocyte maturation in vitro, with the exception of breast cancer, compared to infertile women in the in vitro fertilization program. What is known already Vitrification and storage of oocytes in liquid nitrogen is one of the real options for maintaining reproductive function in cancer patients. Despite careful hormonal stimulation of the ovaries, however, the proportion of oocytes is immature and lost to the patient. In vitro maturation of oocytes can play an important role in resolving immature oocytes and increasing the chances of conception in cancer patients. Moreover, it can mean a safe way to store oocytes when ovarian hormonal stimulation could worsen the disease. Therefore, the aim of this study was to determine whether different types of cancer affect oocyte in vitro maturation. Study design, size, duration After ovarian stimulation in 18 cancer patients, the number and maturity of oocytes were compared to 21 infertile patients in the IVF program over a three-year period. In both groups, 119 germinal vesicle-GV oocytes were matured in vitro to compare the maturation rate. After IVF in a subset of 17 infertile patients, the fertilization of in vitro and in vivo matured oocytes was compared in the same cycles. The procedure was considered in cancer patients. Participants/materials, setting, methods In this prospective study, forty-five GV oocytes in cancer patients and 74 GV oocytes in infertile patients underwent in vitro maturation procedure. Each oocyte was matured in vitro in the MediCult IVM System by conditioning in LAG medium and maturation for up to 28 hours in IVM medium with added hormones FSH and hCG, in coculture with cumulus cells from mature oocytes in the same patients. Oocytes were fertilized by intracytoplasmic sperm injection (ICSI). Main results and the role of chance After controlled ovarian hormonal stimulation, 198 oocytes were retrieved in cancer patients and 259 oocytes in infertile women and there were no significant differences in the number of retrieved oocytes, proportion of degenerated oocytes and proportion of GV oocytes. In cancer patients, the proportion of oocytes that matured in vitro was lower than in infertile patients (66.0 vs. 80.0%), but the difference was not significant. Among cancer patients, the oocyte maturation rate tended to be lower in patients with breast cancer than in patients with other cancers (54.5% vs. 81.2%; difference not significant). However, in patients with breast cancer, significantly fewer oocytes matured in vitro than in infertile patients (54.5% vs. 80.0%; P &lt; 0.05, Chi-Square test) even though they tended to be younger (29.3 ± 7.4 vs. 33.4 ± 5.0 years; non-significant difference). After in vitro maturation, there was a 13% increase in mature oocyte yield in cancer patients and a 20.1% increase in infertile women with no significant difference observed. After ICSI in a subset of infertile women, there was approximately the same fertilization rate between oocytes matured in vitro and in vivo (55.1% vs. 57.0%) in the same cycles. Limitations, reasons for caution For ICSI in oocytes matured in vitro, we had to use semen collected the day before, while oocytes matured in vivo were fertilized with fresh semen in the same cycle. Therefore, we could not compare the development of embryos in both groups. Wider implications of the findings: In vitro maturation of oocytes in connection with their vitrification or vitrification of embryos after their fertilization appears to be a valuable way to maintain the fertility of young cancer patients, but a worse outcome is expected in breast cancer patients. Trial registration number National Medical Ethical Committee Approval, No. 0120–222/2016–2; KME 115/04/16.


1987 ◽  
Author(s):  
R N I Pietersz ◽  
D de Korte ◽  
D Roos ◽  
H W Reesink

Leukocyte poor platelet concentrates (PC), containing less than 10 leukocytes, prepared from buffycoats can be stored in normal PVC bags for 7 days at 22°C without deterioration of the pH. We assumed that a low number of leukocytes present in the PC, is a critical factor to maintain the pH. To test this hypothesis increasing amounts of leukocytes were added to four groups of three PC with comparable plasma volumes (mean 58.6 ± 0.8 (SD) ml) and platelet concentrations (1.01 ± 0.04×109 /ml). Group I had a leukocyte concentration of 0.14±0.048×106 /ml, group II 1.96±0.09×106 /ml, group III 5.53±0.98×106 /ml, and group IV 13.0±0.93×106 /ml. The PC were stored in normal PVC bags for 7 days at 22°C. Measurements in vitro were performed at day 0, 2, 5 and 7.The initial mean pH value was 7.12±0.02 (SD) for all PC and dropped to 6.89, 6.85, 6.77 and 6.61 for group I to IV respectively, at day 7. A significant correlation (Spearman rank test) between low pH values and high leukocytes was found. The same significant positive correlation was observed between high leukocyte concentrations and high glucose consumption and high lactate production and LDH release during storage.These results show that the amount of leukocytes in PC has a significant contribution to the detrimental effect on pH during platelet storage. It is therefore important to prepare PC with a leukocyte count lower than 10 . Moreover the risk of alloimmunisation against HLA antigens will be diminished.


2020 ◽  
Vol 141 ◽  
pp. 91-97
Author(s):  
Lian Cai ◽  
Yeon-Woo Jeong ◽  
Sang-Hwan Hyun ◽  
Il-Jeoung Yu ◽  
Woo-Suk Hwang ◽  
...  

2011 ◽  
Vol 23 (1) ◽  
pp. 225
Author(s):  
G. K. Deb ◽  
S. R. Dey ◽  
J. I. Bang ◽  
S. J. Cho ◽  
T. H. Kwon ◽  
...  

Cumulus cells (CC) play a critical role in oocyte maturation and fertilization via gap junctions. The oocyte itself maintains CC health to favour oocyte maturation via the secretion of paracrine growth factors. However, the antiapoptotic effects of oocyte-secreted factors follow a gradient from the site of the oocytes. Moreover, degrees of CC apoptosis are inversely related to the in vitro embryo development. Therefore, inhibition of CC apoptosis is important for efficient in vitro embryo development. The beneficial effects of retinoic acid (RA) during in vitro embryo production are well known in different species. However, the effect of RA on CC apoptosis is yet to be elucidated. All-trans RA and 9-cis RA are the natural components of retinoids, and all-trans RA are metabolized to 9-cis RA for physiological function. Therefore, the objective of the present study was to evaluate the effect of 9-cis RA on the mechanism for inhibition of apoptosis in CC. Slaughterhouse cumulus–oocyte complexes (COC) were matured in vitro in TCM-199-based in vitro maturation medium containing 0 or 5 mM 9-cis RA for 23 to 24 h (15 COC/100 μL droplet) at 38.5°C and 5% CO2 in air with maximum humidity. Following in vitro maturation, COC of a droplet were fixed in 4% paraformaldehyde for TUNEL staining using In Situ Cell Death Detection Kit (Roche, Budapest, Hungary). The proportion of apoptotic cells was estimated using Olympus Soft Imaging Solutions GmBH (Olympus, Münster, Germany). The COC of the remaining droplet were denuded. The CC were frozen and stored at –80°C. The CC of 3 different cultures were pooled, and total RNA was extracted using RNeasy Mini Kit (Qiagen, Valencia, CA, USA). Total RNA was reverse transcribed into cDNA using Omniscript Reverse Transcription kit (Qiagen). Relative expression of candidate genes was quantified using SYBER green real-time PCR with ΔΔ CT method. The expression was normalized against β-actin, glyceraldehyde 3-phosphate dehydrogenase, and 18s rRNA genes expression. The PCR efficiencies were calculated using relative calibration curves following 10-fold dilution series at 5 measuring points. Data were analysed for one-way ANOVA. The proportion of apoptotic cells was low in the 9-cis RA group (1.3 v. 3.3% of total CC; P < 0.05). Expression of tumor necrosis factor-α (11.1 v. 1.0; P < 0.001), caspase9 (2.0 v. 1.0; P < 0.01), and caspase3 (2.1 v. 1.0; P < 0.001) genes was down-regulated in the 9-cis RA group, whereas expression of Bcl2 gene was increased (1.0 v. 2.6 fold; P < 0.05). Moreover, the expression of c-fos gene of AP-1 pathway was down-regulated (1.9 v. 1 fold; P < 0.05) in the 9-cis RA group. Retinoic acid suppressed the expression of NF-kB, which in turn inhibits tumor necrosis factor-α-mediated caspase activity. However, the expression of NF-kB in CC was not affected by 9-cis RA (1.1 v. 1.0; P > 0.05). In conclusion, the present study indicated that 9-cis RA may inhibit cumulus cell apoptosis through suppression of AP-1 pathway. This work was partly supported by a scholarship from the BK21 program, the KRF (KRF-2008-211-F00011), the IPET (108068-03-1-SB010), and the KOSEF (10525010001-05N2501-00110).


2014 ◽  
Vol 26 (1) ◽  
pp. 200 ◽  
Author(s):  
C. de Frutos ◽  
R. Vicente-Perez ◽  
P. J. Ross

In vitro maturation (IVM) of oocytes in domestic animals is a widespread practice of research and commercial relevance. Gonadotropic hormones are typically supplemented to the IVM medium to stimulate resumption of meiosis, progression to metaphase II (MII), and oocyte developmental competence. The common use of pituitary-derived products presents 2 problems: contamination from other pituitary hormones and inconsistences from batch-to-batch variation. Recombinant hormones can help circumvent these issues and identify specific gonadotropin requirements for in vitro maturation. The aim of the present study was to determine the effect of supplementing recombinant bovine LH and/or FSH (AspenBio) to the maturation of ovine oocytes in terms of cumulus expansion and progression to the MII stage. Abattoir-derived sheep cumulus–oocyte complexes (COC) were obtained from 1- to 5-mm-diameter antral follicles by ovary slicing. Oocytes with a homogeneous cytoplasm surrounded by at least 3 layers of cumulus cells were selected and cultured in serum-free IVM medium (Cotterill et al. 2012 Reproduction 144, 195–207) at 38.5°C and 5% CO2. The COC obtained from 8 replicates were allocated into 4 experimental groups: (1) no hormones; (2) 1.5 μg mL–1 recombinant bovine LH (rbLH); (3) 1.5 μg mL–1 recombinant bovine FSH (rbFSH); and (4) rbLH and rbFSH. The expansion of cumulus cells was recorded in each group after 24 h of IVM and COC classified as (1) very poor or no cumulus expansion (grade 1); (2) limited cumulus expansion (grade 2); and (3) full cumulus expansion (grade 3). Nuclear maturation in the 4 treatments was evaluated by assessing progression to the MII stage via DNA staining with Hoechst 33342 and fluorescence imaging. The effect of treatment on the observed proportion of MII oocytes was evaluated using a mixed logit model including treatment and replicate as fixed and random effects, respectively. Culture in IVM medium in the absence of gonadotropins or in the presence of rbLH resulted in poor cumulus expansion (grade 1). The supplementation of IVM medium with rbFSH (with or without rbLH) yielded a high degree of cumulus expansion (grades 2–3). Likewise, addition of rbFSH enhanced progression of oocytes to the MII stage, whereas use of rbLH, although it had an effect on progression to MII, did not augment the effect of rbFSH (Table 1). These results indicate that rbFSH is necessary and sufficient to induce sheep oocyte maturation in a high proportion of oocytes. Table 1.Cumulus expansion and oocyte nuclear stage after IVM


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