Effect of Butirolactone I on the gene expression of PTGS2, GREM1 and PFKP of the cumulus cells in bovine in vitro matured oocytes
Bibliographic record
Abstract
A small proportion of bovine in vitro matured oocytes (IVM) has the potential to develop to embryo. Aiming to improve oocyte competence, some inhibitors of cyclin-dependent kinases, such as butirolactone I (BL), have been used to synchronize the nuclear and cytoplasmic maturation of bovine oocytes. Moreover, the cumulus cells (CCs) also play an important role for the acquisition of in vitro oocyte competence. Therefore, the aim of this study was to investigate the gene expression of PTGS2, GREM1 and PFKP in the CCs of in vitro or in vivo matured (IVOM) bovine oocytes. Ovaries were collected from a local slaughterhouse, and the oocytes from the follicles were obtained. Oocytes were randomly divided into 5 groups: I (immature oocytes); II (IVOM); III (IVM); IV (meiosis block, 12h; reversal, 12h); and V (meiosis block, 24h; reversal, 24h). All reagents were purchased from SigmaAldrich (St. Louis, USA), unless otherwise specified. The cumulus-oocytes complexes (COCs) were washed and selected in PBS medium plus 10% FCS (Nutricell®, Campinas, Brazil). The medium 199, supplemented with sodium bicarbonate, sodium pyruvate, penicillin, FSH and LH (Bioniche Inc., Canada), estradiol, cisteamine and 10% FCS was used to IVM. The IVM medium, supplemented with 10 µM of BL, without hormones and FCS, was used to meiosis block. For the IVOM, the estrus of 10 Nelore donor cows were synchronized with progesterone (Primer®, Tecnopec, Brazil), estradiol benzoate (Sincrocio®, Ourofino, Brazil) and cloprostenol sodium (Ciosin®, MSD, Brazil). For super stimulation of the ovaries, FSH was injected (six decreasing doses), and final follicle maturation was induced with gonadorelin (Fertagyl®, Intervet, Brazil). The COCs were obtained through OPU, 19- 20 h after gonadorelin injection. The CCs were removed by several pipetting in PBS medium with 0.1% hyaluronidase. Then, droplets containing only CCs were centrifuged (3,355 x g/10 min) and frozen in total RNA extraction medium. Gene expression was investigated by quantitative RT-PCR, normalized by GAPDH constitutive gene. The results were analyzed using ANOVA and Tukey’s test, with P<0.05 taken as significant. There was no statistical difference among the groups for PTGS2. However, the abundance of transcripts for GREM1 was higher (P<0.05) in the CCs from oocytes from group II than from the other groups. The CCs from group II showed higher (P<0.05) abundance of transcripts for PFKP compared to groups I and IV, with similar results for groups I and IV. In conclusion, the meiosis block with BL did not affect the abundance of transcripts of any gene investigated, however, as a higher GREM1 expression was observed in the CCs from IVOM oocytes, further researches using different compounds for IVM medium may identify pivotal factors that are related with the expression of these genes in CCs.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".