title: Dietary red palm oil supplementation decreases infarct size in cholesterol fed rats.
abstract: OBJECTIVE
  The effect of red palm oil (RPO) supplementation on infarct size after ischaemia/reperfusion in a cholesterol enriched diet-induced hyperlipidemic animal model has not been reported. Previous studies reported results on the effect of RPO in a normal diet, whilst evidence of protection has been linked to improved functional recovery, prosurvival kinase, anti-apoptosis and NO-cGMP. Therefore, we aimed to investigate the effects of dietary RPO supplementation in a cholesterol-enriched diet-induced hyperlipidemic rat model and to investigate the involvement of matrix metalloproteinase 2 (MMP2) inhibition as a possible mechanism of protection.
  
  
  METHODS
  Male Wistar rats were fed either a standard rat chow diet (Norm) or a 2% cholesterol-enriched diet (Chol) for nine weeks. Additionally, two more groups received the same treatment, however, at the week 4, diet was supplemented with RPO for the last five weeks (Norm+RPO and Chol+RPO), respectively. After the feeding period hearts were isolated, perfused according to Langendorff and subjected to 30 minutes of normothermic global ischaemia followed by two hours of reperfusion. Infarct size was measured by 2,3,5-triphenyltetrazolium chloride staining at the end of reperfusion.
  
  
  RESULTS
  Cholesterol-enriched diet increased myocardial infarct size from 23.5±3.0% to 37.2±3.6% (p<0.05) when compared to normal diet. RPO supplementation significantly reduced infarct size either in Norm+RPO or in Chol+RPO (to 9.2±1.0% and 26.9±3.0%), respectively. Infarct size in Chol+RPO was comparable to the Norm group. MMP2 activity before ischaemia was significantly reduced in the Chol+RPO group when compared to the Chol group. However, the MMP2 activity of the hearts of the RPO fed rats was significantly increased when compared to the normal diet group after ischaemia.
  
  
  CONCLUSIONS
  For the first time it was shown that dietary RPO supplementation attenuated the increased susceptibility of the hearts in cholesterol fed rats to ischaemia/reperfusion injury. This was shown by reduced infarct size. For the first time we also show that red palm oil supplementation altered pre-ischaemic levels of MMP-2, which may indicate that myocardial MMP2 may be implicated as a possible role player in RPO mediated protection against ischaemia/reperfusion injury in hearts of cholesterol supplemented rats.
authors.affiliation: Cardiovascular Research Group, University of Szeged, Szeged, Hungary.
authors.forename: Gergo
authors.initials: G
authors.lastname: Szucs
authors.forename: Dirk J
authors.initials: DJ
authors.lastname: Bester
authors.forename: Krisztina
authors.initials: K
authors.lastname: Kupai
authors.forename: Tamas
authors.initials: T
authors.lastname: Csont
authors.forename: Csaba
authors.initials: C
authors.lastname: Csonka
authors.forename: Adriaan J
authors.initials: AJ
authors.lastname: Esterhuyse
authors.forename: Peter
authors.initials: P
authors.lastname: Ferdinandy
authors.forename: Jacques
authors.initials: J
authors.lastname: Van Rooyen
mesh_terms: D000818:Animals; D002784:Cholesterol / Q000008:administration & dosage* / Q000097:blood; D019587:Dietary Supplements; D057075:Enzyme Assays; D066298:In Vitro Techniques; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D015428:Myocardial Reperfusion Injury / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D009206:Myocardium / Q000201:enzymology / Q000473:pathology; D009929:Organ Size / Q000187:drug effects; D000073878:Palm Oil; D010938:Plant Oils / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D014280:Triglycerides / Q000097:blood
chemical_list: D010938:Plant Oils; D014280:Triglycerides; D000073878:Palm Oil; D002784:Cholesterol; D020778:Matrix Metalloproteinase 2; C522363:Mmp2 protein, rat