High carbohydrate and high fat diets protect the heart against ischaemia/reperfusion injury
dc.contributor.author | Salie, Ruduwaan | en_ZA |
dc.contributor.author | Huisamen, Barbara | en_ZA |
dc.contributor.author | Lochner, Amanda | en_ZA |
dc.date.accessioned | 2016-05-03T08:43:27Z | |
dc.date.available | 2016-05-03T08:43:27Z | |
dc.date.issued | 2014-07-18 | |
dc.description | CITATION: Salie, R., Huisamen, B. & Lochner, A. 2014. High carbohydrate and high fat diets protect the heart against ischaemia/reperfusion injury. Cardiovascular Diabetology, 13(109):1-12, doi:10.1186/s12933-014-0109-8. | |
dc.description | The original publication is available at http://cardiab.biomedcentral.com | |
dc.description | Publication of this article was funded by the Stellenbosch University Open Access Fund. | |
dc.description.abstract | Background: Although obesity is still considered a risk factor in the development of cardiovascular disorders, recent studies suggested that it may also be associated with reduced morbidity and mortality, the so-called “obesity paradox”. Experimental data on the impact of diabetes, obesity and insulin resistance on myocardial ischaemia/reperfusion injury are controversial. Similar conflicting data have been reported regarding the effects of ischaemic preconditioning on ischaemia/reperfusion injury in hearts from such animals. The aim of the present study was to evaluate the susceptibility to myocardial ischaemia/reperfusion damage in two models of diet-induced obesity as well as the effect of ischaemic and pharmacological preconditioning on such hearts. Methods: Three groups of rats were fed with: (i) normal rat chow (controls) (ii) a sucrose-supplemented diet (DIO) (iii) a high fat diet (HFD). After 16 weeks, rats were sacrificed and isolated hearts perfused in the working mode and subjected to 35 min regional ischaemia/60 min reperfusion. Endpoints were infarct size and functional recovery. Infarct size was determined, using tetrazolium staining. Activation of PKB/Akt and ERKp44/p42 (RISK pathway) during early reperfusion was determined using Western blot. Statistical evaluation was done using ANOVA and the Bonferroni correction. Results: Infarct sizes of non-preconditioned hearts from the two obese groups were significantly smaller than those of the age-matched controls. Ischaemic as well as pharmacological (beta-adrenergic) preconditioning with a beta2-adrenergic receptor agonist, formoterol, caused a significant reduction in infarct size of the controls, but were without effect on infarct size of hearts from the obese groups. However, ischaemic as well as beta-preconditioning caused an improvement in functional performance during reperfusion in all three groups. A clear-cut correlation between the reduction in infarct size and activation of ERKp44/p42 and PKB/Akt was not observed: The reduction in infarct size observed in the non-preconditioned hearts from the obese groups was not associated with activation of the RISK pathway. However, beta-adrenergic preconditioning caused a significant activation of ERKp44/p42, but not PKB/Akt, in all three groups. Conclusions: Relatively long-term administration of the two obesity-inducing diets resulted in cardioprotection against ischaemia/reperfusion damage. Further protection by preconditioning was, however, without effect on infarct size, while an improvement in functional recovery was observed. | en_ZA |
dc.description.uri | http://cardiab.biomedcentral.com/articles/10.1186/s12933-014-0109-8 | |
dc.description.version | Publisher's version | |
dc.format.extent | 12 pages | |
dc.identifier.citation | Salie, R., Huisamen, B. & Lochner, A. 2014. High carbohydrate and high fat diets protect the heart against ischaemia/reperfusion injury. Cardiovascular Diabetology, 13(109):1-12, doi:10.1186/s12933-014-0109-8. | |
dc.identifier.issn | 1475-2840 (online) | |
dc.identifier.other | doi:10.1186/s12933-014-0109-8 | |
dc.identifier.uri | http://hdl.handle.net/10019.1/98956 | |
dc.language.iso | en_ZA | en_ZA |
dc.publisher | BioMed Central Ltd. | |
dc.rights.holder | Authors retain copyright | |
dc.subject | Obesity paradox | en_ZA |
dc.subject | Heart -- Diseases -- Nutritional aspects | en_ZA |
dc.subject | Cardiotonic agents | en_ZA |
dc.subject | Infarction -- Nutritional aspects | en_ZA |
dc.subject | Diet-induced obesity | en_ZA |
dc.subject | High-fat diet | en_ZA |
dc.subject | RISK pathway | en_ZA |
dc.subject | High-carbohydrate diet | en_ZA |
dc.subject | Coronary heart disease -- Prevention | en_ZA |
dc.title | High carbohydrate and high fat diets protect the heart against ischaemia/reperfusion injury | en_ZA |
dc.type | Article | en_ZA |