IBIMOL   23987
INSTITUTO DE BIOQUIMICA Y MEDICINA MOLECULAR PROFESOR ALBERTO BOVERIS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
(-)-Epicatechin and related procyanidins modulate intracellular clacium and prevented oxidation in Jurkat T cells
Autor/es:
S. V. VERSTRAETEN; G. G. MACKENZIE; C. G. FRAGA; P. I. OTEIZA
Lugar:
Santa Barbara, EEUU
Reunión:
Congreso; Oxygen Club of California 2008 Meeting; 2008
Resumen:
We investigated the effects of (-)-epicatechin (EC), its oligomers,
dimer B2 (B2), and trimer C1 (C1), on calcium mobilization
and cell oxidation. Jurkat T cells were subjected to a calcium
mobilization challenge by replacing Na+ with K+ (K) in the incubation
media. A 200 % increase in intracellular calcium concentration
([Ca]i) was observed, and that effect was prevented by the
presence of inhibitors of calcium mobilization. The preincubation
of the cells in the presence of EC, B2 or C1 prevented K-mediated
increase in [Ca]i. IC50 were 10, 24, and 197 nM for EC, B2 and C1,
respectively. Cell membrane depolarization was affected by K, but
neither inhibitors of calcium mobilization, EC, B2, or C1 modified
the increase in membrane potential. A 98 % increase in cell oxidants
was observed after cell exposure to K. This increase was
prevented by the inhibition of calcium 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 [Ca]i-regulated transcription factor NFAT.
These results indicate that EC and related oligomers, assayed at
physiologically achievable concentrations, can modulate [Ca]i and
then prevent cell oxidation and other calcium-regulated events.+ with K+ (K) in the incubation
media. A 200 % increase in intracellular calcium concentration
([Ca]i) was observed, and that effect was prevented by the
presence of inhibitors of calcium mobilization. The preincubation
of the cells in the presence of EC, B2 or C1 prevented K-mediated
increase in [Ca]i. IC50 were 10, 24, and 197 nM for EC, B2 and C1,
respectively. Cell membrane depolarization was affected by K, but
neither inhibitors of calcium mobilization, EC, B2, or C1 modified
the increase in membrane potential. A 98 % increase in cell oxidants
was observed after cell exposure to K. This increase was
prevented by the inhibition of calcium 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 [Ca]i-regulated transcription factor NFAT.
These results indicate that EC and related oligomers, assayed at
physiologically achievable concentrations, can modulate [Ca]i and
then prevent cell oxidation and other calcium-regulated events.i) was observed, and that effect was prevented by the
presence of inhibitors of calcium mobilization. The preincubation
of the cells in the presence of EC, B2 or C1 prevented K-mediated
increase in [Ca]i. IC50 were 10, 24, and 197 nM for EC, B2 and C1,
respectively. Cell membrane depolarization was affected by K, but
neither inhibitors of calcium mobilization, EC, B2, or C1 modified
the increase in membrane potential. A 98 % increase in cell oxidants
was observed after cell exposure to K. This increase was
prevented by the inhibition of calcium 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 [Ca]i-regulated transcription factor NFAT.
These results indicate that EC and related oligomers, assayed at
physiologically achievable concentrations, can modulate [Ca]i and
then prevent cell oxidation and other calcium-regulated events.i. IC50 were 10, 24, and 197 nM for EC, B2 and C1,
respectively. Cell membrane depolarization was affected by K, but
neither inhibitors of calcium mobilization, EC, B2, or C1 modified
the increase in membrane potential. A 98 % increase in cell oxidants
was observed after cell exposure to K. This increase was
prevented by the inhibition of calcium 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 [Ca]i-regulated transcription factor NFAT.
These results indicate that EC and related oligomers, assayed at
physiologically achievable concentrations, can modulate [Ca]i and
then prevent cell oxidation and other calcium-regulated events.i-regulated transcription factor NFAT.
These results indicate that EC and related oligomers, assayed at
physiologically achievable concentrations, can modulate [Ca]i and
then prevent cell oxidation and other calcium-regulated events.i and
then prevent cell oxidation and other calcium-regulated events.