Oligophosphopeptides derived from egg yolk phosvitin up-regulate gamma-glutamylcysteine synthetase and antioxidant enzymes against oxidative stress in Caco-2 cells.
Previously, we have found phosphopeptides (PPPs) from hen egg yolk phosvitin possess a potent 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 and antioxidant enzymes against oxidative stress in Caco-2 cells using an in vitro model. Treatment of 1 mM H2O2-induced Caco-2 cells with PPPs increased cellular GSH levels, concomitant with a significant increase in gamma-glutamylcysteine synthetase (gamma-GCS) activity and the expression of gamma-GCS heavy subunit mRNA. Furthermore, intracellular glutathione reductase, glutathione S-transferase, and catalase activities were elevated by PPPs. In addition, PPPs with high content of phosphorus showed higher induction of these enzyme activities than PPPs without phosphorus. These data indicate that oligophosphopeptides from hen egg yolk phosvitin can up-regulate cellular GSH biosynthesis-associated enzymes activity and antioxidative activities, which play key roles against tissue oxidative stress in the human intestinal epithelial cells.
Katayama
Shigeru
S
Departments of Food Science and Animal and Poultry Science, University of Guelph, Guelph, Ontario, Canada.
Ishikawa
Shin-Ichi
S
Fan
Ming Z
MZ
Mine
Yoshinori
Y
D000975:Antioxidants / Q000032:analysis*; D018938:Caco-2 Cells; D004530:Egg Yolk / Q000737:chemistry*; D005721:Glutamate-Cysteine Ligase / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D018384:Oxidative Stress / Q000187:drug effects*; D010748:Phosphopeptides / Q000494:pharmacology*; D010774:Phosvitin / Q000737:chemistry*; D015854:Up-Regulation / Q000187:drug effects
D000975:Antioxidants; D010748:Phosphopeptides; D010774:Phosvitin; D005721:Glutamate-Cysteine Ligase