Sulfation of genistein alters its antioxidant properties and its effect on platelet aggregation and monocyte and endothelial function

Biochim Biophys Acta. 2004 Feb 24;1670(3):229-37. doi: 10.1016/j.bbagen.2003.12.008.


Soy isoflavones have been extensively studied because of their possible benefits to human health. Genistein, the major isoflavone aglycone, has received most attention; however, it undergoes extensive metabolism (e.g. conjugation with sulfuric acid) in the gut and liver, which may affect its biological properties. This study investigated the antioxidant activity and free radical-scavenging properties of genistein, genistein-4'-sulfate and genistein-4'-7-disulfate as well as their effect on platelet aggregation and monocyte and endothelial function. Electron spin resonance spectroscopy (ESR) and spin trapping data and other standard antioxidant assays indicated that genistein is a relatively weak antioxidant compared to quercetin and that its sulfated metabolites are even less effective. Furthermore, genistein-4'-sulfate was less potent than genistein, and genistein-4'-7-disulfate even less potent, at inhibiting collagen-induced platelet aggregation, nitric oxide (NO) production by macrophages, and secretion by primary human endothelial cells of monocyte chemoattractant protein 1 (MCP-1), intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1). The current data suggest that sulfation of genistein, with the associated loss of hydroxyl groups, decreases its antioxidant activity and its effect on platelet aggregation, inflammation, cell adhesion and chemotaxis.

Publication types

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

MeSH terms

  • Animals
  • Antioxidants / chemical synthesis*
  • Antioxidants / pharmacology
  • Cell Line
  • Cell Survival
  • Chemokine CCL2 / metabolism
  • Dose-Response Relationship, Drug
  • Electron Spin Resonance Spectroscopy
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism
  • Free Radical Scavengers / chemical synthesis*
  • Genistein / analogs & derivatives*
  • Genistein / chemical synthesis
  • Genistein / pharmacology
  • Humans
  • Macrophages / drug effects
  • Mice
  • Molecular Structure
  • Platelet Aggregation Inhibitors / chemical synthesis*
  • Platelet Aggregation Inhibitors / pharmacology
  • Spin Trapping
  • Sulfur / chemistry*


  • Antioxidants
  • Chemokine CCL2
  • Free Radical Scavengers
  • Platelet Aggregation Inhibitors
  • Sulfur
  • Genistein