(-)-Epicatechin and related procyanidins modulate intracellular calcium and prevent oxidation in Jurkat T cells
- 1 January 2008
- journal article
- research article
- Published by Informa UK Limited in Free Radical Research
- Vol. 42 (10), 864-872
- https://doi.org/10.1080/10715760802471452
Abstract
This study investigated the effects of (-)-epicatechin (EC), its oligomers, dimer B2 (B2) and trimer C1 (C1), on calcium-dependent cell oxidation. Jurkat T cells were subjected to a Ca2+ mobilization challenge by replacing Na+ with K+ in the incubation media. A 249±38% increase in intracellular Ca2+ concentration ([Ca2+]i) was observed and that effect was prevented by the presence of inhibitors of Ca2+ mobilization and entrance. The pre-incubation of the cells in the presence of EC, B2 or C1 prevented K+-mediated increase in [Ca2+]i. IC50 were 10, 24 and 196 nm for EC, B2 and C1, respectively. Cell membrane depolarization was affected by K+, but neither inhibitors of Ca2+ mobilization nor EC, B2 or C1 modified the increase in membrane potential. An 84±7% increase in cell oxidants was observed after cell exposure to K+. This increase was prevented by the inhibition of Ca2+ mobilization, NADPH oxidase and protein kinase C, as well as by 10 nm EC, 10 nm B2 or 100 nm C1. In addition, EC and B2 (100 nm) significantly inhibited the activation of the [Ca2+]i-regulated transcription factor NFAT. These results indicate that EC and related oligomers, assayed at physiologically achievable concentrations, can modulate [Ca2+]i and then prevent cell oxidation and other Ca2+-regulated events.Keywords
This publication has 43 references indexed in Scilit:
- Calcium signaling in lymphocytesCurrent Opinion in Immunology, 2008
- Regulation of Nox and Duox enzymatic activity and expressionFree Radical Biology & Medicine, 2007
- Plant polyphenols: How to translate their in vitro antioxidant actions to in vivo conditionsIUBMB Life, 2007
- Procyanidins protect Caco-2 cells from bile acid- and oxidant-induced damageFree Radical Biology & Medicine, 2006
- Antioxidant and Membrane Effects of Procyanidin Dimers and Trimers Isolated from Peanut and CocoaJournal of Agricultural and Food Chemistry, 2005
- Store-Operated Calcium ChannelsPhysiological Reviews, 2005
- Phospholipase C, protein kinase C, Ca2+/calmodulin‐dependent protein kinase II, and redox state are involved in epigallocatechin gallate‐induced phospholipase D activation in human astroglioma cellsEuropean Journal of Biochemistry, 2004
- Calcium Signaling Mechanisms in T LymphocytesAnnual Review of Immunology, 2001
- Artifacts in Cell Culture: Rapid Generation of Hydrogen Peroxide on Addition of (−)-Epigallocatechin, (−)-Epigallocatechin Gallate, (+)-Catechin, and Quercetin to Commonly Used Cell Culture MediaBiochemical and Biophysical Research Communications, 2000
- A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye bindingAnalytical Biochemistry, 1976