Comparative analysis of trans-fats and alpha-linolenic acid administration on cardiomyocyte viability during ischemia/reperfusion injury
Notice bibliographique
Résumé
Ischemic heart disease is the largest cause of death due to cardiovascular origins. A better understanding of the mechanisms responsible for ischemic heart disease increases the potential for therapies. This will lead to decreased mortalities in Canada and around the world. Nutritional interventions have gained increasing attention as causes or treatments for cardiovascular disease. For example, trans fats (TFAs) have both beneficial and deleterious effects on cardiovascular disease [1]. In this study, we would like to examine this phenomenon. We contrast the effects of two different TFAs on cardiomyocyte viability. We compare the industrially produced trans-fat elaidic acid (EA) and the ruminant trans-fat vaccenic acid (VA) on apoptotic and autophagic markers during non-ischemic (control), ischemic (ISCH) and ischemia/reperfusion (IR) conditions. Rat cardiomyocytes are exposed to medium containing fatty acids conjugated with bovine serum albumin for 24 hours. VA and EA have no significant effect on biomarkers of apoptosis or cell death. Interestingly, a similar effect is observed with autophagic and apoptotic markers of LDLr-/- mice whose diets were supplemented with VA or EA. Cells pre-treated with EA prior to 60 minutes of simulated ISCH and 120 minutes of IR increased cell death compared to control through augmented apoptosis. VA decreases the number of dead cells during ISCH and IR. However, the apoptotic parameters remain unchanged. We also observe that VA decreases oxidized phospholipid content in non-ischemic conditions. We conclude that not all TFAs are deleterious to the heart. EA is toxic to cardiomyocytes with or without ISCH or IR whereas VA is cardioprotective during IR and ISCH conditions. We believe VA decreases oxidized phospholipid content to produce this cardioprotective effect. For the purposes of comparison, we examined the effects of α-linolenic acid (ALA), an essential polyunsaturated fatty acid found in foods like flaxseed. Omega-3 fatty acids have been associated with improved cardiovascular outcomes. Here, isolated adult rat cardiomyocytes from male Sprague Dawley rats were exposed to medium containing ALA for 24 hours and then exposed control, ISCH or IR conditions. Cell death increases during ISCH and IR. An increase in DNA fragmentation and caspase-3 activity was observed in both the ISCH and IR conditions. Pre-treatment of the cells with ALA subsequently inhibits cell death during ISCH and IR challenge and significantly reduced both DNA fragmentation and caspase-3 cleavage during ISCH and IR. Cardiomyocyte resting Ca2+ increased and Ca2+ transients decreased during ISCH or I/R but ALA pre-treatment did not improve either parameter significantly. We hypothesize that apoptosis is initiated through phosphatidylcholine oxidation within the cardiomyocytes. Pre-treatment of cells with ALA resulted in a significant incorporation of ALA within cardiomyocyte phosphatidylcholine. Two pro-apoptotic oxidized phosphatidylcholine (OxPC) species, 1-palmitoyl-2-(5'-oxo-valeroyl)-sn-glycero-3-phosphocholine (POVPC) and 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine (PGPC) were significantly increased during both ISCH and IR. ALA pre-treatment significantly decreased the production of POVPC and PGPC during ISCH and I/R. It is concluded that ALA protects the cardiomyocyte from apoptotic cell death during simulated ISCH and IR by inhibiting the production of specific pro-apoptotic OxPC species. In summary, we observe a differential effect of ALA, VA and EA on parameters of cardiomyocyte viability during ISCH or IR.
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 machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| 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 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 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 source (Gemma direct ou Codex distillé), 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 ».