title: Tocotrienol rich fraction (TRF) supplementation protects against oxidative DNA damage and improves cognitive functions in Wistar rats.
abstract: OBJECTIVE
  Oxidative stress is caused by imbalance between the productions of reactive oxygen species (ROS) and antioxidant defense mechanisms. Palm oil antioxidants such as tocotrienol rich fraction (TRF) is known to have neuroprotective effects on neurones by acting against free radical induced neuronal cell death. This study was undertaken to elucidate the effect of TRF on oxidative DNA damage and cognitive functions in experimental rats.
  
  
  METHODS
  A total of 20 male Wistar rats (aged 3 months) were divided into 2 groups: (i) control group fed with distilled water and (ii) experimental group fed with TRF (200 mg/ kg body weight) for 8 months. DNA damage was determined using Comet assay. Antioxidant enzymes like superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were assessed in the blood. The Morris Water Maze (MWM) test was used to evaluate the cognitive functions.
  
  
  RESULTS
  DNA damage was significantly reduced in the experimental group supplemented with TRF compared to the control group (p <0.05). In the group supplemented with TRF, the percentage of DNA damage was 2.87 ± 0.48% compared to 5.96 ± 0.43% in the control group. SOD, GPx, and CAT enzyme activities increased in experimental group. Results from MWM showed improvement in cognitive functions as determined by latency to target platform, swim path and average speed between TRF and control groups.
  
  
  CONCLUSIONS
  Continuous supplementation of TRF for 8 months reduced DNA damage and exhibited positive influence in spatial learning and memory.
authors.affiliation: Departments of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.
authors.forename: N M
authors.initials: NM
authors.lastname: Taridi
authors.forename: M F
authors.initials: MF
authors.lastname: Yahaya
authors.forename: S L
authors.initials: SL
authors.lastname: Teoh
authors.forename: A A
authors.initials: AA
authors.lastname: Latiff
authors.forename: W Z Wan
authors.initials: WZ
authors.lastname: Ngah
authors.forename: S
authors.initials: S
authors.lastname: Das
authors.forename: M
authors.initials: M
authors.lastname: Mazlan
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D003071:Cognition / Q000187:drug effects*; D004249:DNA Damage / Q000187:drug effects*; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D024508:Tocotrienols / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D024508:Tocotrienols