title: The effects of palm oil tocotrienol-rich fraction supplementation on biochemical parameters, oxidative stress and the vascular wall of streptozotocin-induced diabetic rats.
abstract: OBJECTIVE
  This study examined the effects of palm oil tocotrienol-rich fractions on streptozotocin-induced diabetic rats.
  
  
  METHODS
  Animals were divided into three groups: (i) normal non-diabetic (NDM), (ii) diabetic treated (tocotrienol-rich fractions - TRF) and (iii) diabetic untreated (non-TRF). The treatment group received oral administration of tocotrienol-rich fractions (200 mg/kg body weight) daily for eight weeks. The normal non-diabetic and the diabetic untreated groups were fed standard rat feed. Blood glucose and lipid profiles, oxidative stress markers and morphological changes of the thoracic aorta were evaluated.
  
  
  RESULTS
  Tocotrienol-rich fractions treatment reduced serum glucose and glycated hemoglobin concentrations. The tocotrienol-rich fractions group also showed significantly lower levels of plasma total cholesterol, low-density lipoprotein cholesterol, and triglyceride, as compared to the untreated group. The tocotrienol-rich fractions group had higher levels of high-density lipoprotein cholesterol, as compared to the untreated group. Superoxide dismutase activity and levels of vitamin C in plasma were increased in tocotrienol-rich fractions-treated rats. The levels of plasma and aorta malondealdehyde + 4-hydroxynonenal (MDA + 4-HNE) and oxidative DNA damage were significant following tocotrienol-rich fractions treatment. Electron microscopic examination showed that the normal morphology of the thoracic aorta was disrupted in STZ-diabetic rats. Tocotrienol-rich fractions supplementation resulted in a protective effect on the vessel wall.
  
  
  CONCLUSIONS
  These results show that tocotrienol-rich fractions lowers the blood glucose level and improves dyslipidemia. Levels of oxidative stress markers were also reduced by administration of tocotrienol-rich fractions. Vessel wall integrity was maintained due to the positive effects mediated by tocotrienol-rich fractions.
authors.affiliation: Department of Biomedical Science, Faculty of Allied Health Sciences, Universiti Kebangsaan, Malaysia.
authors.forename: Siti Balkis
authors.initials: SB
authors.lastname: Budin
authors.forename: Faizah
authors.initials: F
authors.lastname: Othman
authors.forename: Santhana Raj
authors.initials: SR
authors.lastname: Louis
authors.forename: Mokhtar Abu
authors.initials: MA
authors.lastname: Bakar
authors.forename: Srijit
authors.initials: S
authors.lastname: Das
authors.forename: Jamaludin
authors.initials: J
authors.lastname: Mohamed