Relación entre el índice lipoproteínas de baja densidad (LDL)/lipoproteínas de alta densidad (HDL) con enzimas antioxidantes y el índice oxLDL/HDL.

INTRODUCTION: The low-density lipoprotein (LDL)/high-density lipoprotein (HDL) index is a predictive factor for atherosclerosis, which is associated with oxidative modifications. OBJECTIVE: To assess the association of the index with oxidative stress markers. METHODS: 444 subjects were included and were clinically, anthropometrically and biochemically characterized; superoxide dismutase, glutathione peroxidase 3 (GPx3), magnesium and oxidized LDL (oxLDL) index (oxLDL/HDL) were quantified. RESULTS: A decrease of 1.014 units in the LDL/HDL index was associated with a superoxide dismutase increase of 1 unit/mL (p = 0.030), while a decrease of 0.023 units was associated with a GPx3 increase of 1 nmol/min/mL (p < 0.0005). An increase of one unit in the index was associated with an increase of 0.831 in the oxLDL/HDL index (p < 0.05). After controlling for the effect of gender, age, smoking, obesity and insulin resistance, a reduction of 0.001 per index unit was associated with an increase of 1 µg/g of magnesium in the nails (p = 0.020). CONCLUSIONS: The LDL/HDL index shows an inverse relationship with the antioxidant status and a direct relationship with oxidation status, regardless of other cardiovascular and oxidative stress risk factors.

INTRODUCCIÓN: El índice de lipoproteínas de baja densidad (LDL)/lipoproteínas de alta densidad (HDL) es un factor predictivo de aterosclerosis, la cual está asociada con modificaciones oxidativas. OBJETIVO: Evaluar la asociación del índice con marcadores de estrés oxidativo. MÉTODO: Se incluyeron 444 sujetos, caracterizados clínica, antropométrica y bioquímicamente; se cuantificó superóxido dismutasa, glutation peroxidasa 3 (GPx3), magnesio e índice LDL oxidadas (oxLDL/HDL). RESULTADOS: La disminución en 1.014 unidades del índice LDL/HDL se asoció con aumento de 1 unidad/mL de superóxido dismutasa (p = 0.030) y la de 0.023 unidades con aumento de 1 nmol/minuto/mL de GPx3 (p < 0.0005). El aumento en 1 unidad del índice se asoció con aumento de 0.831 unidades en el índice oxLDL/HDL (p < 0.05). Después de controlar el efecto del sexo, edad, fumar, obesidad y resistencia a la insulina, la reducción de 0.001 por unidad del índice se asoció con aumento de 1 µg/g de magnesio en uñas (p = 0.020). CONCLUSIONES: El índice LDL/HDL presenta relación inversa con el estado antioxidante y relación directa con el estado de oxidación, independientemente de otros factores de riesgo cardiovascular y de estrés oxidativo.

Relationship of the low-density lipoprotein (LDL)/high-density lipoprotein (HDL) index with antioxidant enzymes and with the oxLDL/HDL index

Introduction: The low-density lipoprotein (LDL)/high-density lipoprotein (HDL) index is a predictive factor for atherosclerosis, which is associated with oxidative modifications. Objective: To assess the association of the index with oxidative stress markers. Methods: 444 subjects were included and were clinically, anthropometrically and biochemically characterized; superoxide dismutase, glutathione peroxidase 3 (GPx3), magnesium and oxidized LDL (oxLDL) index (oxLDL/HDL) were quantified. Results: A decrease of 1.014 units in the LDL/HDL index was associated with a superoxide dismutase increase of 1 unit/mL (p = 0.030), while a decrease of 0.023 units was associated with a GPx3 increase of 1 nmol/min/mL (p < 0.0005). An increase of one unit in the index was associated with an increase of 0.831 in the oxLDL/HDL index (p < 0.05). After controlling for the effect of gender, age, smoking, obesity and insulin resistance, a reduction of 0.001 per index unit was associated with an increase of 1 µg/g of magnesium in the nails (p = 0.020). Conclusions: The LDL/HDL index shows an inverse relationship with the antioxidant status and a direct relationship with oxidation status, regardless of other cardiovascular and oxidative stress risk factors.

Relationship of the low-density lipoprotein (LDL)/high-density lipoprotein (HDL) index with antioxidant enzymes and with the oxLDL/HDL index.

INTRODUCTION: The low-density lipoprotein (LDL)/high-density lipoprotein (HDL) index is a predictive factor for atherosclerosis, which is associated with oxidative modifications. OBJECTIVE: To assess the association of the index with oxidative stress markers. METHODS: 444 subjects were included and were clinically, anthropometrically and biochemically characterized; superoxide dismutase, glutathione peroxidase 3 (GPx3), magnesium and oxidized LDL (oxLDL) index (oxLDL/HDL) were quantified. RESULTS: A decrease of 1.014 units in the LDL/HDL index was associated with a superoxide dismutase increase of 1 unit/mL (p = 0.030), while a decrease of 0.023 units was associated with a GPx3 increase of 1 nmol/min/mL (p < 0.0005). An increase of one unit in the index was associated with an increase of 0.831 in the oxLDL/HDL index (p < 0.05). After controlling for the effect of gender, age, smoking, obesity and insulin resistance, a reduction of 0.001 per index unit was associated with an increase of 1 µg/g of magnesium in the nails (p = 0.020). CONCLUSIONS: The LDL/HDL index shows an inverse relationship with the antioxidant status and a direct relationship with oxidation status, regardless of other cardiovascular and oxidative stress risk factors.

Alternative Splicing as a Target for Cancer Treatment.

Alternative splicing is a key mechanism determinant for gene expression in metazoan. During alternative splicing, non-coding sequences are removed to generate different mature messenger RNAs due to a combination of sequence elements and cellular factors that contribute to splicing regulation. A different combination of splicing sites, exonic or intronic sequences, mutually exclusive exons or retained introns could be selected during alternative splicing to generate different mature mRNAs that could in turn produce distinct protein products. Alternative splicing is the main source of protein diversity responsible for 90% of human gene expression, and it has recently become a hallmark for cancer with a full potential as a prognostic and therapeutic tool. Currently, more than 15,000 alternative splicing events have been associated to different aspects of cancer biology, including cell proliferation and invasion, apoptosis resistance and susceptibility to different chemotherapeutic drugs. Here, we present well established and newly discovered splicing events that occur in different cancer-related genes, their modification by several approaches and the current status of key tools developed to target alternative splicing with diagnostic and therapeutic purposes.

Potassium Current Is Not Affected by Long-Term Exposure to Ghrelin or GHRP-6 in Somatotropes GC Cells.

Ghrelin is a growth hormone (GH) secretagogue (GHS) and GHRP-6 is a synthetic peptide analogue; both act through the GHS receptor. GH secretion depends directly on the intracellular concentration of Ca(2+); this is determined from the intracellular reserves and by the entrance of Ca(2+) through the voltage-dependent calcium channels, which are activated by the membrane depolarization. Membrane potential is mainly determined by K(+) channels. In the present work, we investigated the effect of ghrelin (10 nM) or GHRP-6 (100 nM) for 96 h on functional expression of voltage-dependent K(+) channels in rat somatotropes: GC cell line. Physiological patch-clamp whole-cell recording was used to register the K(+) currents. With Cd(2+) (1 mM) and tetrodotoxin (1 µ m) in the bath solution recording, three types of currents were characterized on the basis of their biophysical and pharmacological properties. GC cells showed a K(+) current with a transitory component (I A) sensitive to 4-aminopyridine, which represents ~40% of the total outgoing current; a sustained component named delayed rectifier (I K), sensitive to tetraethylammonium; and a third type of K(+) current was recorded at potentials more negative than -80 mV, permitting the entrance of K(+) named inward rectifier (KIR). Chronic treatment with ghrelin or GHRP-6 did not modify the functional expression of K(+) channels, without significant changes (P < 0.05) in the amplitudes of the three currents observed; in addition, there were no modifications in their biophysical properties and kinetic activation or inactivation.