Angel Hernández - Academia.edu (original) (raw)
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Papers by Angel Hernández
Cell Death & …, 2010
Transient reactive oxygen species (ROS) production is currently proving to be an important mechan... more Transient reactive oxygen species (ROS) production is currently proving to be an important mechanism in the regulation of intracellular signalling, but reports showing the involvement of ROS in important biological processes, such as cell differentiation, are scarce. In this study, we show for the first time that ROS production is required for megakaryocytic differentiation in K562 and HEL cell lines and also in human CD34 þ cells. ROS production is transiently activated during megakaryocytic differentiation, and such production is abolished by the addition of different antioxidants (such as N-acetyl cysteine, trolox, quercetin) or the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor diphenylene iodonium. The inhibition of ROS formation hinders differentiation. RNA interference experiments have shown that a p22 phoxdependent NADPH oxidase activity is responsible for ROS production. In addition, the activation of ERK, AKT and JAK2 is required for differentiation, but the activation of phosphatidylinositol 3-kinase and c-Jun N-terminal kinase seems to be less important. When ROS production is prevented, the activation of these signalling pathways is partly inhibited. Taken together, these results show that NADPH oxidase ROS production is essential for complete activation of the main signalling pathways involved in megakaryocytopoiesis to occur. We suggest that this might also be important for in vivo megakaryocytopoiesis.
Neuroscience Letters, 1995
The efficacy of acetylcholine muscarinic M2 receptor-G-protein coupling was investigated in Alzhe... more The efficacy of acetylcholine muscarinic M2 receptor-G-protein coupling was investigated in Alzheimer's disease and control neocortical membranes by measuring the effects of MgC12 and 5'-guanylylimidodiphosphate (Gpp[NH]p) on high-affinity [3H]oxotremorine-M ([3H]OXO-M) binding. MgC12 gave similar enhancements of [3H]OXO-M binding in Alzheimer's disease and control occipital cortex. In contrast, MgC12 enhanced [3H]OXO-M binding was significantly higher in Alzheimer's disease superior temporal cortex, compared to controls. MgCl* enhanced [3H]OXO-M binding in both the occipital and temporal cortices of the Alzheimer's disease cases was reversed to control levels by Gpp[NH]p. It is concluded that the number of high-affinity muscarinic M2 sites is increased in Alzheimer's disease superior temporal, but not occipital, cortex and that M2 sites in both regions maintain an efficient Gprotein coupling.
Cell Death & …, 2010
Transient reactive oxygen species (ROS) production is currently proving to be an important mechan... more Transient reactive oxygen species (ROS) production is currently proving to be an important mechanism in the regulation of intracellular signalling, but reports showing the involvement of ROS in important biological processes, such as cell differentiation, are scarce. In this study, we show for the first time that ROS production is required for megakaryocytic differentiation in K562 and HEL cell lines and also in human CD34 þ cells. ROS production is transiently activated during megakaryocytic differentiation, and such production is abolished by the addition of different antioxidants (such as N-acetyl cysteine, trolox, quercetin) or the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor diphenylene iodonium. The inhibition of ROS formation hinders differentiation. RNA interference experiments have shown that a p22 phoxdependent NADPH oxidase activity is responsible for ROS production. In addition, the activation of ERK, AKT and JAK2 is required for differentiation, but the activation of phosphatidylinositol 3-kinase and c-Jun N-terminal kinase seems to be less important. When ROS production is prevented, the activation of these signalling pathways is partly inhibited. Taken together, these results show that NADPH oxidase ROS production is essential for complete activation of the main signalling pathways involved in megakaryocytopoiesis to occur. We suggest that this might also be important for in vivo megakaryocytopoiesis.
Neuroscience Letters, 1995
The efficacy of acetylcholine muscarinic M2 receptor-G-protein coupling was investigated in Alzhe... more The efficacy of acetylcholine muscarinic M2 receptor-G-protein coupling was investigated in Alzheimer's disease and control neocortical membranes by measuring the effects of MgC12 and 5'-guanylylimidodiphosphate (Gpp[NH]p) on high-affinity [3H]oxotremorine-M ([3H]OXO-M) binding. MgC12 gave similar enhancements of [3H]OXO-M binding in Alzheimer's disease and control occipital cortex. In contrast, MgC12 enhanced [3H]OXO-M binding was significantly higher in Alzheimer's disease superior temporal cortex, compared to controls. MgCl* enhanced [3H]OXO-M binding in both the occipital and temporal cortices of the Alzheimer's disease cases was reversed to control levels by Gpp[NH]p. It is concluded that the number of high-affinity muscarinic M2 sites is increased in Alzheimer's disease superior temporal, but not occipital, cortex and that M2 sites in both regions maintain an efficient Gprotein coupling.