Phosphopeptides derived from egg yolk phosvitin up-regulate γ-glutamylcysteine synthetase and antioxidant enzymes against oxidative stress in human intestinal epithelial cells

AGFD 72

Shigeru Katayama, katayama@uoguelph.ca1, Ming Z. Fan, mfan@uoguelph.ca2, Shinichi Ishikawa, sishikawa@uoguelph.ca1, and Yoshinori Mine, ymine@uoguelph.ca1. (1) Department of Food Science, University of Guelph, Guelph, ON N1G 2W1, Canada, (2) Department of Animal and Poultry Science, University of Guelph, Guelph, ON N1G 2W1, Canada
Oxidative stress is a state characterized by an excess of reactive oxygen species (ROS) in the body. Stress damaged intestinal epithelial cells (gut inflammatory disorder) is associated with many chronic diseases and the mucosal immune responses. Recently, we have developed phosphopeptides (PPPs) from hen egg yolk phosvitin and found PPPs possess a novel antioxidative activity against oxidative stress in human intestinal epithelial cells, Caco-2. However, their biological activity at the cellular level has not yet fully understood. The objective of this study is to evaluate the regulation of glutathione (GSH) biosynthesis-associated enzymes against oxidative stress in Caco-2 cells. Treatment of 1mM H2O2-induced cells with PPPs increased GSH levels and γ-glutamylcysteine synthetase. Furthermore, intracellular catalase, glutathione reductase, and glutathione S-transferase activities were elevated by addition of PPPs. These data indicate that PPPs can up-regulate cellular GSH biosynthesis-associated enzymes activity, which play key roles against tissue oxidative stress in the human intestinal epithelial cells.
 

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1:00 PM-3:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Poster

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Division of Agricultural & Food Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006