title: Effect of the tocotrienol-rich fraction on the lifespan and oxidative biomarkers in Caenorhabditis elegans under oxidative stress.
abstract: OBJECTIVE
  This study was performed to determine the effect of the tocotrienol-rich fraction on the lifespan and oxidative status of C. elegans under oxidative stress.
  
  
  METHODS
  Lifespan was determined by counting the number of surviving nematodes daily under a dissecting microscope after treatment with hydrogen peroxide and the tocotrienol-rich fraction. The evaluated oxidative markers included lipofuscin, which was measured using a fluorescent microscope, and protein carbonyl and 8-hydroxy-2'-deoxyguanosine, which were measured using commercially available kits.
  
  
  RESULTS
  Hydrogen peroxide-induced oxidative stress significantly decreased the mean lifespan of C. elegans, which was restored to that of the control by the tocotrienol-rich fraction when administered before or both before and after the hydrogen peroxide. The accumulation of the age marker lipofuscin, which increased with hydrogen peroxide exposure, was decreased with upon treatment with the tocotrienol-rich fraction (p<0.05). The level of 8-hydroxy-2'-deoxyguanosine significantly increased in the hydrogen peroxide-induced group relative to the control. Treatment with the tocotrienol-rich fraction before or after hydrogen peroxide induction also increased the level of 8-hydroxy-2'-deoxyguanosine relative to the control. However, neither hydrogen peroxide nor the tocotrienol-rich fraction treatment affected the protein carbonyl content of the nematodes.
  
  
  CONCLUSIONS
  The tocotrienol-rich fraction restored the lifespan of oxidative stress-induced C. elegans and reduced the accumulation of lipofuscin but did not affect protein damage. In addition, DNA oxidation was increased.
authors.affiliation: Universiti Kebangsaan Malaysia, Department of Biochemistry, Faculty of Medicine, Kuala Lumpur City Campus, 50300 Kuala Lumpur/Malaysia. joaan@medic.ukm.my
authors.forename: Goon Jo
authors.initials: GJ
authors.lastname: Aan
authors.forename: Mohd Shahril Aszrin
authors.initials: MS
authors.lastname: Zainudin
authors.forename: Noralisa Abdul
authors.initials: NA
authors.lastname: Karim
authors.forename: Wan Zurinah Wan
authors.initials: WZ
authors.lastname: Ngah
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D017173:Caenorhabditis elegans / Q000187:drug effects* / Q000502:physiology; D004249:DNA Damage / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008062:Lipofuscin / Q000378:metabolism; D008136:Longevity / Q000187:drug effects*; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D013997:Time Factors; D024508:Tocotrienols / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D008062:Lipofuscin; D024508:Tocotrienols