Crosstalk Between Nitric Oxide and Endocannabinoid Signaling Pathways in Normal and Pathological Placentation.

Endocannabinoids are a group of endogenous lipid mediators that act as ligands of cannabinoid and vanilloid receptors, activating multiple signal transduction pathways. Together with enzymes responsible for their synthesis and degradation, these compounds constitute the endocannabinoid system (ECS), which is involved in different physiological processes in reproduction. The placenta, which is essential for the success of gestation and optimal fetal growth, undergoes constant tissue remodeling. ECS members are expressed in trophoblast cells, and current evidence suggests that this system is involved in placental development, apoptosis, and syncytialization. Impairment of endocannabinoid signaling has been associated with several pathological conditions such as intrauterine growth restriction and preeclampsia. Both clinical entities are characterized by dysregulation on vascular perfusion where nitrergic system performs a pivotal role. Nitric oxide (NO) is a potent local vasodepressor that exerts a critical role in the regulation of hemodynamic flow, contributing to the maintenance of low vascular resistance in the feto-placental circulation. NO production could be affected by different factors and growing evidence suggests that the endocannabinoid mediators may regulate nitrergic signaling. Herein, we review emerging knowledge supporting ECS-mediated regulation of NO production in normal placentation. Finally, we discuss how alterations in these systems could affect homoeostasis and contribute to the occurrence of placental-mediated pregnancy complications. Given the impact on women and perinatal heath, we will focus on current knowledge regarding the effects of ECS on nitrergic system in normal and pathological placentation.

New Insights Into the Role of Placental Aquaporins and the Pathogenesis of Preeclampsia.

Accumulated evidence suggests that an abnormal placentation and an altered expression of a variety of trophoblast transporters are associated to preeclampsia. In this regard, an abnormal expression of AQP3 and AQP9 was reported in these placentas. Recent data suggests that placental AQPs are not only water channel proteins and that may participate in relevant processes required for a normal placental development, such as cell migration and apoptosis. Recently we reported that a normal expression of AQP3 is required for the migration of extravillous trophoblast (EVT) cells. Thus, alterations in this protein might lead to an insufficient transformation of the maternal spiral arteries resulting in fluctuations of oxygen tension, a potent stimulus for oxidative damage and trophoblast apoptosis. In this context, the increase of oxygen and nitrogen reactive species could nitrate AQP9, producing the accumulation of a non-functional protein affecting the survival of the villous trophoblast (VT). This may trigger the exacerbated release of apoptotic VT fragments into maternal circulation producing the systemic endothelial dysfunction underlying the maternal syndrome. Therefore, our hypothesis is that the alteration in the expression of placental AQPs observed at the end of gestation may take place during the trophoblast stem cell differentiation, disturbing both EVT and VT cells development, or during the VT differentiation and turnover. In both situations, VT is affected and at last the maternal vascular system is activated leading to the clinical manifestations of preeclampsia.

Performance of the GHQ-12 in relation to current and lifetime CIDI psychiatric diagnoses

Antecedentes. La validez del Cuestionario General de Salud (versión de 12 reactivos), CGS-12, como instrumento útil para detectar los probables casos en la práctica médica general, ha sido recientemente objeto de un estudio muy extenso en diferentes países. Sin embargo, la puntuación general es sólo un aspecto de las cualidades del instrumento y se ha sugerido que deberian estudiarse las respuestas específicas a los reactivos, en virutud de que en ellos se consideran aspectos tanto positivos como negativos en relación con la salud mental, así como explotar la estructura factorial del instrumento en diferentes culturas. Método. En este trabajo se estudió la validez del CGS-12 utilizándolo como criterio externo de la Entrevista Internacional Diagnóstica Compuesta (CIDI), permitiendo que la definición de caso se hiciera con base en dos sistemas de clasificación, y la información se analizara no sólo en relación con la psicopatología presente en el momento de la entrevista, sino también en relación con la existencia de trastornos psiquiátricos alguna vez en la vida. Este abordaje constituye una aproximación diferente y original respecto de los otros estudios. El funcionamiento de cada reactivo se ilustró por medio de gráficas ROC, y su asociación se midió en términos del odds ratio; finalmente, se obtuvieron las estructuras factoriales. Resultados. Las coeficientes de validez para el instrumento en general fueron similares a los obtenidos en otros estudios. El análisis del funcionamiento de cada reactivo mostró que los primeros cuatro sólo se asociaron significativamente con la presencia de psicopatolgía al momento del estudio, mientras que los ocho reactivos restantes se asociaron con la presencia de trastornos en la vida. El análisis factorial con rotación varimax identificó tres factores que explican el 59 por ciento de la varianza para los casos actuales, mientras que para los trastornos en la vida, dos factores explicaron el 45 por ciento de la varianza...