CEFYBO   02669
CENTRO DE ESTUDIOS FARMACOLOGICOS Y BOTANICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Alteration induced by zinc deficiency in normal and tumor T lymphocyte activity through the differential modulation of protein kinase C (PKC) isoenzymes.
Autor/es:
ANDRÉS ORQUEDA; MARÍA LAURA BARREIRO ARCOS; HORACIO TORTI; MIRIAM WALD; ANA MARÍA GENARO; GRACIELA ALICIA CREMASCHI
Lugar:
Buenos Aires, Argentina
Reunión:
Congreso; XXII Latinoamerican and First Ibero-American Congress of Physiological Sciences; 2006
Institución organizadora:
Sociedad Argentina de Fisiología
Resumen:
Zinc deficiency has known effects on immune responses but the mechanisms involved are being studied. Here we study the effect of Zn deficiency in normal and tumor T lymphocytes and the role of PKC, a crucial enzyme for lymphocyte activation. Concanavalin A-stimulated T lymphocytes or T lymphoma cells (LBC and BW 5147) were cultured in the absence or presence of specific intra-(TPEN) or extracellular (DTPA) Zn chelators and the proliferation, PKC activity and PKC isoenzymes pattern were evaluated. Both TPEN and DTPA inhibited normal and LBC cell proliferation,  effect reverted by Zn addition. On BW they also inhibited growth to a lesser extent,  actions not modified by exogenous Zn. DTPA lowered intracellular Zn content, effect  impaired by Zn addition, as measured by atomic absorption spectroscopy. Proliferative actions of TPEN were accompanied by a decreased in PKC activation. Also, a decrease in PKC a and q isoforms both in normal T and LBC cells treated with the chelators was found. However, only on normal lymphocytes an increase in the atypical PKC z  isoform was  observed. These results show that Zn plays an  role in normal and tumor lymphocyte growth, and that its deficiency would alter the expression of key PKC isoenzymes.