Hv1 increased activity is asssociated to a high glycolitic flux

VENTURA, CLARA; ENRIQUE, NICOLÁS JORGE; MARTÍN, PEDRO; FELICE, JUAN IGNACIO; ISSOURIBEHERE, DIEGO; ASUAJE, AGUSTÍN; MILESI, VERÓNICA

Congreso; Reunión Anual de Sociedades de Biociencias; 2020

Sociedad Argentina de Investigación Clínica (SAIC), Sociedad Argentina de Inmunología (SAI) y Sociedad Argentina de Fisiología (SAFIS)

It is well-known that most of cancer cells present an increased glycolytic flow related to their metabolic reprogramming (Tanner et al., 2018). This metabolic change, considered an emerging hallmark of cancer, conduces to an exacerbated lactate secretion and produces large amounts of protons. We have previously demonstrated that the inhibition of Hv1, an ion channel capable to extrude H+ of cells, induces intracellular acidification and apoptosis in leukemic Jurkat T cells (Asuaje et al., 2018). In this work we present evidences showing that Jurkat T cells cultivated in presence of high (25 mM) glucose concentration increases (15%, p<0.01; N=9) lactate secretion per cell (commercial kit) compared with the cells cultivated in physiologic (5.5 mM) glucose concentration, suggesting that, the high glucose concentration in the culture medium increases the glycolytic flow. Then, we studied in deep the role of Hv1 channel in this metabolic context observing that the cells cultivated in presence of glucose 25 mM increases Hv1 channel activity (3 fold of ion current increment, p<0.001, N=10) measured by patch clamp technique; intracellular pH (0.12 units of pH increment, p<0.01, N=2) determined by using BCECF-AM prove; and cell proliferation (20% of increment, p<0.01, N=3. Doubling time). Moreover, when the same parameters were evaluated in presence of a specific Hv1 channel  blocker  (ClGBI,  200 µM),  we  found  that  ClGBI  produced  a  drop of intracellular  pH  (p<0.01,  N=2),  a  slight  decrease  of  extracellular  lactate concentration (25%, p<0.05 vs. DMSO 0.2%, N=4) and a significantly increase of cell death (p<0.05, anexineV-IP). These results suggest that high concentration of glucose induces an increment of glycolytic rate and cell proliferation in Jurkat T cells, and both of them were diminished by Hv1 inhibition, showing a relevant function of Hv1 channel in the metabolic change of these cells.