125 SWINE EMBRYOS WITH HIGH POTENTIAL TO DEVELOP IN VITRO HAVE LESS ?H2A.X AND MORE NBS1 PROTEINS
Notice bibliographique
Résumé
The developmental potential of embryos produced in vitro is lower than those produced in vivo. The artificial environment and the stressful conditions of culture may affect embryo development through various mechanisms including DNA damage and, consequently, cell death. We hypothesized that the developmental competence of in vitro-cultured embryos is influenced by mechanisms signalling DNA damage and repair processes. Therefore, the aim of the study was to assess these processes by systematic quantification of phosphorylated histone H2A.X (?H2A.X) and p95 or nibrin protein (NSB1) in early- and late-cleaved swine embryos cultured in vitro. Studies from several groups including ours have demonstrated superior in vitro development for early-cleaved (within 24 h of culture) compared with late-cleaved (between 24 and 48 h) embryos. The presence of ?H2A.X is associated with the DNA double-strand breaks, and NBS1 is involved in the process of DNA damage repair. These proteins were detected by both immunofluorescence and western blotting. Swine embryos were produced by parthenogenetic activation using in vitro-matured oocytes. Oocyte maturation, activation, and embryo culture were conducted as previously described (Che L et al. 2007 Theriogenology 67 1297-1304). At 24 and 48 h after activation, embryos were categorized as early- and late-cleaved, and were collected for protein detection on D2-3, D4-5, or D6-7 of culture. A minimum of 3 replicates were performed per treatment. The amount of protein in relation to the ß-actin at D2-3, D4-5, and D6-7 as revealed by western blotting was 76.4% ± 1.3, 63.3% ± 10.5, and 43.2% ± 11.2 for ?H2A.X and 60.2% ± 4.2, 67.3% ± 13.2, and 61.3% ± 6.2 for NBS1, respectively. Comparisons between early and late-cleaved groups were then performed by immunoflorescence detection of both proteins. Differences between groups were verified using Student’s t-test. The average proportion of cells that were positively stained for ?H2AX at D2-3, D4-5, and D6-7 of culture was 64.4% ± 2.6 (n = 178) v. 65.92% ± 3.7 (n = 114; P = 0.7), 55.7% ± 2.4 (n = 121) v. 59.8% ± 4.7 (n = 62; P = 0.4) and 29.1% ± 2.1 (n = 137) v. 43.5% ± 3.4 (n = 41; P = 0.001), for early v. late-cleaved embryos. The values for NSB1 staining were 13.9% ± 3.8 (75) v. 3.9% ± 3.0 (34; P = 0.09), 50.5% ± 4.2 (66) v. 35.8% ± 6.0 (33; P = 0.05), and 51.0% ± 4.5 (n = 54) v. 38.2% ± 5.5 (n = 24; P = 0.1). These findings confirm the presence of ?H2A.X and NBS1 proteins in swine embryos during all stages of in vitro culture. We further show that early cleaved embryos have a lower proportion of ?H2A.X and a higher proportion of NSB1-positive cells compared with late-cleaved embryos. Together, these findings suggest that early cleaved embryos that have a superior capacity for in vitro development are better prepared to repair DNA damage during in vitro culture. Supported by NSERC.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».