Increased cyclic guanosine monophosphate production and endothelial nitric oxide synthase level in mononuclear cells from sildenafil citrate-treated patients with erectile dysfunction.

Mononuclear cells express enzymes involved in the NO/cyclic guanosine monophosphate (cGMP) generating system, as well as PDE5. The objective of the study was to determine the effect of sildenafil citrate administration on the level of proteins involved in the NO/cGMP generating system in mononuclear cells from patients with ED. Twenty-one patients with ED (International Index of Erectile Function-Erectile Function Domain (IIEF-EFD) 17.9+/-0.8) were enrolled and 100 mg sildenafil citrate on-demand was administered during 12 weeks. All patients showed cardiovascular risk factors. After sildenafil citrate administration, IIEF-EFD score was improved (26+/-1.2 P<0.05). In the mononuclear cells, the protein level of endothelial NO synthase (eNOS) was higher after sildenafil citrate treatment. It was accompanied by reduction in the circulating plasma levels of both high-sensitive C-reactive protein and soluble intercellular adhesive molecule-1. The protein level of soluble guanylate cyclase and PDE5 did not change in the mononuclear cells after sildenafil citrate treatment. However, in the mononuclear cells exogenous NO induced a higher cGMP production after 12-weeks sildenafil citrate administration. In conclusion, in mononuclear cells from patients with ED sildenafil citrate administration increased the level of eNOS protein and increased cGMP production in response to NO. Moreover, sildenafil citrate administration reduced the plasma circulating levels of two biomarkers associated with inflammation.

Aspectos proteómicos y genéticos de la resistencia a la aspirina / Proteomics and genetics aspects of aspirin resistance

Objetivo: Analizar si existe alguna asociación entre la resistencia a aspirina (RA) y la presencia de polimorfismos genéticos de un único nucleótido (SNPs) en el gen de la COX-1, así como su relación con modificaciones en la expresión de proteínas plasmáticas en pacientes con enfermedad isquémica estable y tratamiento continuado de aspirina. Materiales y métodos: Analizamos el proteoma plasmático de 19 pacientes sensibles, 19 resistentes. RA se definió mediante el sistema PFA-100. Se realizó electroforesis bidimensional (IPG 17cm, pH(4-7), geles SDS-PAGE 10%) y tinción con plata. Se analizaron cambios en tres SNPs (A-842G, C22T y C50T) en 50 pacientes sensibles, 33 resistentes y 83 controles mediante PCR a tiempo real. Resultados: La expresión de cuatro isoformas de alfa1-antitripsina estaba aumentada en los pacientes resistentes. No encontramos diferencias en la expresión de ceruloplasmina, precursor de haptoglobina, apolipoproteína AI y precursor de albúmina entre ambos tipos de pacientes. Ningún paciente presentó cambios en el SNP A-842G. La frecuencia de cambio en C22T y C50T fue relativamente baja con respecto a la población total. Conclusiones: No encontramos asociación entre la presencia de polimorfismos en el gen de la COX-1 y la peor respuesta a la aspirina. Los cambios en observados alfa1-antitripsina podrían estar relacionados con un diferente estado inflamatorio entre ambos tipos de pacientes (AU)

Aim: To evaluate the existence of a possible association between Aspirin resistance (AR), COX-1 single-nucleotide polymorphisms (SNPs) and the modifications in the plasma proteome of clinically stable coronary patients. Materials and methods: AR was defined according to the PFA-100 assay. AR-sensitive and AR-resistant patients had been taken aspirin for the last 9 months. The proteomic study (19 AR-sensitive, 19 AR-resistant) was performed using IPG strips (17cm, pH 4-7), SDS-PAGE gels (10%) and silver staining. We study three SNPs (A- 842G, C22T y C50T) in 50 AR-sensitive patients, 33 AR-resistant and 83 controls using a real-time PCR. Results: The expression of four alpha1-antitripsin isoforms was increased in the aspirin-resistant patients. No differences were found in the expression of ceruloplasmin, haptoglobin-precursor, apolipoprotein-AI and albumin- precursor between both groups of patients. The A-842G SNP was undetectable in all subjects. The remaining two SNPs (C22T y C50T) showed a low frequency with respect the global population. Conclusions: The low SNPs frequencies were unlikely to explain the difference in aspirin responsiveness between both groups of patients. The changes in alpha1-antitripsin could be linked with a different inflammatory state in these patients (AU)

Soluble guanylate cyclase beta1-subunit expression is increased in mononuclear cells from patients with erectile dysfunction.

The aim was to determine in circulating mononuclear cells from patients with erectile dysfunction (ED), the level of expression of endothelial nitric oxide synthase (eNOS), soluble guanylate cyclase (sGC) beta1-subunit and phosphodiesterase type-V (PDE-V). Peripheral mononuclear cells from nine patients with ED of vascular origin and nine patients with ED of neurological origin were obtained. Fourteen age-matched volunteers with normal erectile function were used as control. Reduction in eNOS protein was observed in the mononuclear cells from patients with ED of vascular origin but not in those from neurological origin. Although sGC beta1-subunit expression was increased in mononuclear cells from patients with ED, the sGC activity was reduced. However, only the patients with ED of vascular origin showed an increased expression of PDE-V. This work shows for the first time that, independently of the aetiology of ED, the expression of sGC beta1-subunit was increased in circulating mononuclear cells; however, the expression of both eNOS and PDE-V was only modified in the circulating mononuclear cells from patients with ED of vascular origin.

Involvement of endothelium and endothelin-1 in lead-induced smooth muscle cell dysfunction in rats.

Lead exposure induces dysfunction of the cyclic guanosine monophosphate-dependent vasodilator system through downregulation of soluble guanylate cyclase (sGC) expression. The endothelium not only releases vasodilators but also vasoconstrictors such as endothelin-1 (ET-1). Our aim was to explore the role of the vascular endothelium and ET-1 as possible mediators of lead-induced downregulation of sGC. Isolated aortic segments from Wistar Kyoto rats were incubated in the presence or absence of lead (1 parts per million) for 24 h. Endothelium was mechanically removed in some of the aorta segments. As reported previously, lead exposure induced downregulation of sGC protein expression in the intact aortic segments. However, lead exposure failed to significantly modify sGC-beta1 subunit expression in the endothelium-denuded aortic segments. Incubation with a selective ETA-type receptor inhibitor, BQ-123 (10(-6) mol/l), restored sGC protein expression in lead-exposed intact aortic segments. As it has also been previously observed, incubation in lead-containing medium resulted in the upregulation of cyclooxygenase-2 (COX-2) in the intact aortic segments. Denudation of endothelium partially abrogated this effect of lead. Incubation with BQ-123 prevented the lead-induced upregulation COX-2 in the intact aortic segments. However, neither ET-1 content nor ETA-type receptor expression were modified by lead exposure of the aortic segments. As conclusion, the endothelium through the activation of ETA-type receptors mediates the downregulation of sGC expression by lead in the vascular wall.