Specific cellular responses to alpha-tocopherol

J Nutr. 2000 Jul;130(7):1649-52. doi: 10.1093/jn/130.7.1649.

Abstract

In the last 10 years precise cellular functions of alpha-tocopherol, some of which are independent of its antioxidant/radical-scavenging ability, have been revealed. Absorption of alpha-tocopherol from the gut is a selective process. Other tocopherols are not absorbed or are absorbed to a lesser extent. At the post-translational level, alpha-tocopherol inhibits protein kinase C and 5-lipoxygenase and activates protein phosphatase 2A and diacylglycerol kinase. Some genes [platelet glycoprotein IV/thrombospondin receptor/class B scavenger receptor (CD36), alpha-tocopherol transfer protein (alpha-TTP), alpha-tropomyosin, connective tissue growth factor and collagenase] are affected by alpha-tocopherol at the transcriptional level. alpha-Tocopherol also inhibits cell proliferation, platelet aggregation, monocyte adhesion and the oxygen burst in neutrophils. Other antioxidants, such as beta-tocopherol and probucol, do not mimic these effects, suggesting a nonantioxidant, alpha-tocopherol-specific molecular mechanism.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Cell Adhesion / drug effects
  • Cell Division / drug effects
  • Diacylglycerol Kinase / metabolism
  • Enzyme Activation
  • Humans
  • Lipoxygenase Inhibitors
  • Phosphoprotein Phosphatases / metabolism
  • Platelet Aggregation / drug effects
  • Protein Kinase C / antagonists & inhibitors
  • Protein Phosphatase 2
  • Protein Processing, Post-Translational / drug effects
  • Reactive Oxygen Species / metabolism
  • Transcription, Genetic / drug effects
  • Vitamin E / pharmacology*

Substances

  • Lipoxygenase Inhibitors
  • Reactive Oxygen Species
  • Vitamin E
  • Diacylglycerol Kinase
  • Protein Kinase C
  • Phosphoprotein Phosphatases
  • Protein Phosphatase 2