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Human immunodeficiency virus (HIV) infection is an established risk factor for pulmonary arterial hypertension (PAH); however, the pathogenesis of HIV-related PAH remains unclear. Since K+ channel dysfunction is a common marker in most forms of PAH, our aim was to analyze whether the expression of HIV proteins is associated with impairment of K+ channel function in the pulmonary vascular bed. HIV transgenic mice (Tg26) expressing seven of the nine HIV viral proteins and wild-type (WT) mice were used. Hemodynamic assessment was performed by echocardiography and catheterization. Vascular reactivity was studied in endothelium-intact pulmonary arteries. K+ currents were recorded in freshly isolated pulmonary artery smooth muscle cells (PASMC) using the patch-clamp technique. Gene expression was assessed using quantitative RT-PCR. PASMC from Tg26 mice had reduced K+ currents and were more depolarized than those from WT. Whereas voltage-gated K+ channel 1.5 (Kv1.5) currents were preserved, pH-sensitive noninactivating background currents (IKN) were nearly abolished in PASMC from Tg26 mice. Tg26 mice had reduced lung expression of Kv7.1 and Kv7.4 channels and decreased responses to the Kv7.1 channel activator L-364,373 assessed by vascular reactivity and patch-clamp experimental approaches. Although we found pulmonary vascular remodeling and endothelial dysfunction in Tg26 mice, this was not accompanied by changes in hemodynamic parameters. In conclusion, the expression of HIV proteins in vivo impairs pH-sensitive IKN and Kv7 currents. This negative impact of HIV proteins in K+ channels was not sufficient to induce PAH, at least in mice, but may play a permissive or accessory role in the pathophysiology of HIV-associated PAH., Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Our study determines alterations in the vasoconstrictor response elicited by electric field stimulation (EFS) in mesenteric arteries from cirrhotic rats treated with CCl(4), and how calcitonin gene-related peptide (CGRP) participates in this response. Vasoconstriction induced by EFS was analysed in the absence and presence of the CGRP receptor antagonist CGRP(8-37) in arterial segments from control and cirrhotic rats. The vasodilator response to exogenous CGRP was tested in both groups of rats, and the interference of the guanylate cyclase inhibitor ODQ or the K(ATP) channel blocker glibenclamide was analysed only in segments from cirrhotic rats. The vasodilator response to the K(ATP) channel opener pinacidil and to 8-bromo-cyclic GMP was tested. The K(ATP) currents were recorded using the patch-clamp technique. Expression of receptor activity-modifying protein 1 (RAMP1), calcitonin receptor-like receptor, Kir 6.1 and sulfonylurea receptor 2B (SUR2B) was also analysed. Release of CGRP and cGMP was measured. The EFS-elicited vasoconstriction was less in segments from cirrhotic rats. The presence of CGRP(8-37) increased the EFS-induced response only in segments from cirrhotic rats. The CGRP-induced vasodilatation was greater in segments from cirrhotic rats, and was inhibited by ODQ or glibenclamide. Both pinacidil and 8-bromo-cyclic GMP induced a stronger vasodilator response in segments from cirrhotic rats. Pinacidil induced greater K(ATP) currents in cirrhotic myocytes. Expression of RAMP1, calcitonin receptor-like receptor, Kir 6.1 and SUR2B was not modified by liver cirrhosis. Liver cirrhosis increased CGRP release, but did not modify cGMP formation. The decreased vasoconstrictor response to EFS in cirrhosis is mediated by increased vasodilator response to CGRP, as well as increased K(ATP) channel gating. This effect of CGRP may play a role in the splanchnic vasodilatation present in liver cirrhosis., Instituto de Salud Carlos III Spanish Government DEP2006-56187-C04-04, Ministerio de Ciencia e Innovación (SAF09-10374), Depto. de Biología Celular, Fac. de Odontología, TRUE, pub

Aims: A variety of vessels, such as resistance pulmonary arteries (PA) and fetoplacental arteries and the ductus arteriosus (DA) are specialized in sensing and responding to changes in oxygen tension. Despite opposite stimuli, normoxic DA contraction and hypoxic fetoplacental and PA vasoconstriction share some mechanistic features. Activation of neutral sphingomyelinase (nSMase) and subsequent ceramide production has been involved in hypoxic pulmonary vasoconstriction (HPV). Herein we aimed to study the possible role of nSMase-derived ceramide as a common factor in the acute oxygen-sensing function of specialized vascular tissues. Results: The nSMase inhibitor GW4869 and an anticeramide antibody reduced the hypoxic vasoconstriction in chicken PA and chorioallantoic arteries (CA) and the normoxic contraction of chicken DA. Incubation with interference RNA targeted to SMPD3 also inhibited HPV. Moreover, ceramide and reactive oxygen species production were increased by hypoxia in PA and by normoxia in DA. Either bacterial sphingomyelinase or ceramide mimicked the contractile responses of hypoxia in PA and CA and those of normoxia in the DA. Furthermore, ceramide inhibited voltage-gated potassium currents present in smooth muscle cells from PA and DA. Finally, the role of nSMase in acute oxygen sensing was also observed in human PA and DA. Innovation: These data provide evidence for the proposal that nSMase-derived ceramide is a critical player in acute oxygen-sensing in specialized vascular tissues. Conclusion: Our results indicate that an increase in ceramide generation is involved in the vasoconstrictor responses induced by two opposite stimuli, such as hypoxia (in PA and CA) and normoxia (in DA)., Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Current approved therapies for pulmonary hypertension (PH) aim to restore the balance between endothelial mediators in the pulmonary circulation. These drugs may exert vasodilator effects on poorly oxygenated vessels. This may lead to the derivation of blood perfusion towards low ventilated alveoli, i.e., producing ventilation-perfusion mismatch, with detrimental effects on gas exchange. The aim of this study is to analyze the oxygen-sensitivity in vitro of 25 drugs currently used or potentially useful for PH. Additionally, the study analyses the effectiveness of these vasodilators in the pulmonary vs the systemic vessels. Vasodilator responses were recorded in pulmonary arteries (PA) and mesenteric arteries (MA) from rats and in human PA in a wire myograph under different oxygen concentrations. None of the studied drugs showed oxygen selectivity, being equally or more effective as vasodilators under conditions of low oxygen as compared to high oxygen levels. The drugs studied showed low pulmonary selectivity, being equally or more effective as vasodilators in systemic than in PA. A similar behavior was observed for the members within each drug family. In conclusion, none of the drugs showed optimal vasodilator profile, which may limit their therapeutic efficacy in PH., Ministerio de Economía, Comercio y Empresa, Instituto de Salud Carlos III, Unión Europea, Fundación contra la Hipertensión Pulmonar, Universidad Complutense de Madrid, Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Background Pulmonary hypertension (PH) is frequently observed in patients with acute respiratory distress syndrome (ARDS) and it is associated with an increased risk of mortality. Both acid sphingomyelinase (aSMase) activity and interleukin 6 (IL-6) levels are increased in patients with sepsis and correlate with worst outcomes, but their role in pulmonary vascular dysfunction pathogenesis has not yet been elucidated. Therefore, the aim of this study was to determine the potential contribution of aSMase and IL-6 in the pulmonary vascular dysfunction induced by lipopolysaccharide (LPS). Methods Rat or human pulmonary arteries (PAs) or their cultured smooth muscle cells (SMCs) were exposed to LPS, SMase or IL-6 in the absence or presence of a range of pharmacological inhibitors. The effects of aSMase inhibition in vivo with D609 on pulmonary arterial pressure and inflammation were assessed following intratracheal administration of LPS. Results LPS increased ceramide and IL-6 production in rat pulmonary artery smooth muscle cells (PASMCs) and inhibited pulmonary vasoconstriction induced by phenylephrine or hypoxia (HPV), induced endothelial dysfunction and potentiated the contractile responses to serotonin. Exogenous SMase and IL-6 mimicked the effects of LPS on endothelial dysfunction, HPV failure and hyperresponsiveness to serotonin in PA; whereas blockade of aSMase or IL-6 prevented LPS-induced effects. Finally, administration of the aSMase inhibitor D609 limited the development of endotoxin-induced PH and ventilation-perfusion mismatch. The protective effects of D609 were validated in isolated human PAs. Conclusions Our data indicate that aSMase and IL-6 are not simply biomarkers of poor outcomes but pathogenic mediators of pulmonary vascular dysfunction in ARDS secondary to Gram-negative infections., Instituto de Salud Carlos III, Ministro de Economía y comptetividad, Comisión Europea, Reintegración Europea Marie Curie, Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Introduction Current treatment with vasodilators for pulmonary hypertension associated with respiratory diseases is limited by their inhibitory effect on hypoxic pulmonary vasoconstriction (HPV) and uncoupling effects on ventilation-perfusion (V’/Q’). Hypoxia is also a well-known modulator of the nitric oxide (NO) pathway, and may therefore differentially affect the responses to phosphodiesterase 5 (PDE5) inhibitors and soluble guanylyl cyclase (sGC) stimulators. So far, the effects of the sGC stimulator riociguat on HPV have been poorly characterized. Materials and methods Contraction was recorded in pulmonary arteries (PA) in a wire myograph. Anesthetized rats were catheterized to record PA pressure. Ventilation and perfusion were analyzed by micro-CT-SPECT images in rats with pulmonary fibrosis induced by bleomycin. Results The PDE5 inhibitor sildenafil and the sGC stimulator riociguat similarly inhibited HPV in vitro and in vivo. Riociguat was more effective as vasodilator in isolated rat and human PA than sildenafil. Riociguat was ≈3-fold more potent under hypoxic conditions and it markedly inhibited HPV in vivo at a dose that barely affected the thromboxane A2 (TXA2) mimetic U46619-induced pressor responses. Pulmonary fibrosis was associated with V’/Q’ uncoupling and riociguat did not affect the V’/Q’ ratio. Conclusion PDE5 inhibitors and sGC stimulators show a different vasodilator profile. Riociguat was highly effective and potentiated by hypoxia in rat and human PA. In vivo, riociguat preferentially inhibited hypoxic than non-hypoxic vasoconstriction. However, it did not worsen V’/Q’ coupling in a rat model of pulmonary fibrosis., Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Quercetin is a dietary flavonoid which exerts vasodilator, antiplatelet and antiproliferative effects and reduces blood pressure, oxidative status and end-organ damage in humans and animal models of systemic hypertension. We hypothesized that oral quercetin treatment might be protective in a rat model of pulmonary arterial hypertension. Three weeks after injection of monocrotaline, quercetin (10 mg/kg/d per os) or vehicle was administered for 10 days to adult Wistar rats. Quercetin significantly reduced mortality. In surviving animals, quercetin decreased pulmonary arterial pressure, right ventricular hypertrophy and muscularization of small pulmonary arteries. Classic biomarkers of pulmonary arterial hypertension such as the downregulated expression of lung BMPR2, Kv1.5, Kv2.1, upregulated survivin, endothelial dysfunction and hyperresponsiveness to 5-HT were unaffected by quercetin. Quercetin significantly restored the decrease in Kv currents, the upregulation of 5-HT2A receptors and reduced the Akt and S6 phosphorylation. In vitro, quercetin induced pulmonary artery vasodilator effects, inhibited pulmonary artery smooth muscle cell proliferation and induced apoptosis. In conclusion, quercetin is partially protective in this rat model of PAH. It delayed mortality by lowering PAP, RVH and vascular remodeling. Quercetin exerted effective vasodilator effects in isolated PA, inhibited cell proliferation and induced apoptosis in PASMCs. These effects were associated with decreased 5-HT2A receptor expression and Akt and S6 phosphorylation and partially restored Kv currents. Therefore, quercetin could be useful in the treatment of PAH., Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Objective—Voltage-dependent K+ (Kv) channels from the Kv7 family are expressed in blood vessels and contribute to cardiovascular physiology. Although Kv7 channel blockers trigger muscle contractions, Kv7 activators act as vasorelaxants. Kv7.1 and Kv7.5 are expressed in many vessels. Kv7.1 is under intense investigation because Kv7.1 blockers fail to modulate smooth muscle reactivity. In this study, we analyzed whether Kv7.1 and Kv7.5 may form functional heterotetrameric channels increasing the channel diversity in vascular smooth muscles. Approach and Results—Kv7.1 and Kv7.5 currents elicited in arterial myocytes, oocyte, and mammalian expression systems suggest the formation of heterotetrameric complexes. Kv7.1/Kv7.5 heteromers, exhibiting different pharmacological characteristics, participate in the arterial tone. Kv7.1/Kv7.5 associations were confirmed by coimmunoprecipitation, fluorescence resonance energy transfer, and fluorescence recovery after photobleaching experiments. Kv7.1/Kv7.5 heterotetramers were highly retained at the endoplasmic reticulum. Studies in HEK-293 cells, heart, brain, and smooth and skeletal muscles demonstrated that the predominant presence of Kv7.5 stimulates release of Kv7.1/Kv7.5 oligomers out of lipid raft microdomains. Electrophysiological studies supported that KCNE1 and KCNE3 regulatory subunits further increased the channel diversity. Finally, the analysis of rat isolated myocytes and human blood vessels demonstrated that Kv7.1 and Kv7.5 exhibited a differential expression, which may lead to channel diversity. Conclusions—Kv7.1 and Kv7.5 form heterotetrameric channels increasing the diversity of structures which fine-tune blood vessel reactivity. Because the lipid raft localization of ion channels is crucial for cardiovascular physiology, Kv7.1/Kv7.5 heteromers provide efficient spatial and temporal regulation of smooth muscle function. Our results shed light on the debate about the contribution of Kv7 channels to vasoconstrictio, Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

The Coronavirus Disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and its sublineages pose a new challenge to healthcare systems worldwide due to its ability to efficiently spread in immunized populations and its resistance to currently available therapies. COVID-19, although targeting primarily the respiratory system, is also now well established that later affects every organ in the body. Most importantly, despite the available therapy and vaccine-elicited protection, the long-term consequences of viral infection in breakthrough and asymptomatic individuals are areas of concern. In the past two years, investigators accumulated evidence on how the virus triggers our immune system and the molecular signals involved in the cross-talk between immune cells and structural cells in the pulmonary vasculature to drive pathological lung complications such as endothelial dysfunction and thrombosis. In the review, we emphasize recent updates on the pathophysiological inflammatory and immune responses associated with SARS-CoV-2 infection and their potential long-term consequences that may consequently lead to the development of pulmonary vascular diseases., Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Aims Voltage-gated potassium channels encoded by KCNQ genes (Kv7 channels) are emerging as important regulators of vascular tone. In this study, we analysed the contribution of Kv7 channels to the vasodilation induced by hypoxia and the cyclic AMP pathway in the coronary circulation. We also assessed their regional distribution and possible impairment by diabetes. Methods and results We examined the effects of Kv7 channel modulators on K+ currents and vascular reactivity in rat left and right coronary arteries (LCAs and RCAs, respectively). Currents from LCA were more sensitive to Kv7 channel inhibitors (XE991, linopirdine) and activators (flupirtine, retigabine) than those from RCA. Accordingly, LCAs were more sensitive than RCAs to the relaxation induced by Kv7 channel enhancers. Likewise, relaxation induced by the adenylyl cyclase activator forskolin and hypoxia, which were mediated through Kv7 channel activation, were greater in LCA than in RCA. KCNQ1 and KCNQ5 expression was markedly higher in LCA than in RCA. After incubation with high glucose (HG, 30 mmol/L), myocytes from LCA, but not from RCA, were more depolarized and showed reduced Kv7 currents. In HG-incubated LCA, the effects of Kv7 channel modulators and forskolin were diminished, and the expression of KCNQ1 and KCNQ5 was reduced. Finally, vascular responses induced by Kv7 channel modulators were impaired in LCA, but not in RCA, from type 1 diabetic rats. Conclusion Our results reveal that the high expression and function of Kv7 channels in the LCA and their down-regulation by diabetes critically determine the sensitivity to key regulators of coronary tone., Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Reduced expression and/or activity of Kv1.5 channels (encoded byKCNA5) is a common hallmark in human or experimentalpulmonary arterial hypertension (PAH). Likewise, genetic variantsinKCNA5have been found in patients with PAH, but theirfunctional consequences and potential impact on the disease arelargely unknown. Herein, this study aimed to characterize thefunctional consequences of sevenKCNA5variants found in a cohortof patients with PAH. Potassium currents were recorded by patch-clamp technique in HEK293 cells transfected with wild-type ormutant Kv1.5 cDNA. Flow cytometry, Western blot, and confocalmicroscopy techniques were used for measuring protein expressionand cell apoptosis in HEK293 and human pulmonary artery smoothmuscle cells.KCNA5variants (namely, Arg184Pro and Gly384Arg)found in patients with PAH resulted in a clear loss of potassiumchannel function as assessed by electrophysiological and molecular modeling analyses. The Arg184Pro variant also resulted in apronounced reduction of Kv1.5 expression. Transfection withArg184Pro or Gly384Arg variants decreased apoptosis ofhuman pulmonary artery smooth muscle cells compared withthe wild-type cells, demonstrating thatKCNA5dysfunction inboth variants affects cell viability. Thus, in addition toaffecting channel activity, both variants were associated withimpaired apoptosis, a crucial process linked to the disease. Theestimated prevalence of dysfunctionalKCNA5variants in thePAH population analyzed was around 1%. The data indicatethat someKCNA5variants found in patients with PAH havecritical consequences for channel function, supporting the ideathatKCNA5pathogenic variants may be a causative orcontributing factor for PAH., Unión Europea, Federación Española de Enfermedades Raras, Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Horizonte 2020. Marie-Curie Nº 847635., Recent evidence suggests that vitamin D is involved in the development of pulmonary arterial hypertension (PAH). The aim of this study was to analyze the electrophysiological and contractile properties of pulmonary arteries (PAs) in vitamin D receptor knockout mice (Vdr−/−). PAs were dissected and mounted in a wire myograph. Potassium membrane currents were recorded in freshly isolated PA smooth muscle cells (PASMCs) using the conventional whole-cell configuration of the patch-clamp technique. Potential vitamin D response elements (VDREs) in Kv7 channels coding genes were studied, and their protein expression was analyzed. Vdr−/− mice did not show a pulmonary hypertensive phenotype, as neither right ventricular hypertrophy nor endothelial dysfunction was apparent. However, resistance PA from these mice exhibited increased response to retigabine, a Kv7 activator, compared to controls and heterozygous mice. Furthermore, the current sensitive to XE991, a Kv7 inhibitor, was also higher in PASMCs from knockout mice. A possible VDRE was found in the gene coding for KCNE4, the regulatory subunit of Kv7.4. Accordingly, Vdr−/− mice showed an increased expression of KCNE4 in the lungs, with no changes in Kv7.1 and Kv7.4. These results indicate that the absence of Vdr in mice, as occurred with vitamin D deficient rats, is not sufficient to induce PAH. However, the contribution of Kv7 channel currents to the regulation of PA tone is increased in Vdr−/− mice, resembling animals and humans suffering from PAH., European Commission, Instituto de Salud Carlos III (España), Agencia Estatal de Investigación (España), Universidad Complutense de Madrid, Depto. de Farmacología y Toxicología, Depto. de Fisiología, Fac. de Medicina, TRUE, pub, Descuento UCM

El proyecto propone la elaboración de nuevos casos clínicos que asemejen situaciones reales sobre los que los estudiantes puedan desarrollar un aprendizaje autónomo dirigido por el profesorado en función de los conceptos que sean de interés para cada grupo farmacológico y acercándole a la situación más cercana a su práctica profesional. Los objetivos del proyecto son: 1) Generar una base de nuevos casos clínicos dirigidos a que los estudiantes trabajen sobre grupos de fármacos en un contexto lo más real posible. Los diferentes casos que se elaboren en este proyecto podrán ser utilizados en la docencia de diversas asignaturas impartidas por miembros del departamento de Farmacología y Toxicología. Las sesiones dirigidas al estudio basado en la resolución de casos se plantean como una herramienta docente que tiene como finalidad el desarrollo de competencias transversales como promover la motivación, el trabajo en equipo, la participación de los estudiantes en los debates, así como, fomentar el pensamiento crítico y el conocimiento del método científico. Este tipo de aprendizaje en contexto facilita la integración de los conocimientos y su mayor retención además de la dotar a los estudiantes con las habilidades para fomentar un aprendizaje continuo. 2) Apoyar la formación del profesorado de reciente incorporación, así como del personal investigador que participan como colabores en tareas docentes del departamento y que podrían ser potenciales futuros docentes.

La cirrosis es el estadio final de una serie de enfermedades hepáticas crónicas, que conllevan una elevada morbilidad y mortalidad. Además, la cirrosis hepática puede dar lugar a dos complicaciones vasculares pulmonares específicas: El síndrome hepatopulmonar (SHP) y la hipertensión portopulmonar (HPP). Se estima que el SHP y la HPP se desarrollan en aproximadamente el 30% y el 5-10%, respectivamente, de los pacientes con enfermedad hepática crónica y cirrosis. El SHP se asocia a dilataciones vasculares intrapulmonares, la formación de derivaciones (shunts) y el desarrollo de hipoxemia grave; mientras que la HPP se caracteriza por fenómenos de proliferación, vasoconstricción, remodelado vascular e hipertensión pulmonar en presencia de hipertensión portal. La falta de modelos animales adecuados es una limitación importante para el estudio de estas enfermedades.Cada vez más evidencias sugieren que las vesículas extracelulares (VEs) pueden contribuir al desarrollo de enfermedades pulmonares. Las VEs son un grupo heterogéneo de estructuras nanométricas membranosas derivadas de las células. Están presentes en todos los fluidos biológicos y participan en múltiples procesos fisiológicos y patológicos. La importancia de las VEs radica en su capacidad de transferir información a otras células, influyendo así en la función de la célula receptora. Las VEs pueden trasportar todas las diferentes categorías de biomoléculas (proteínas, ácidos nucleicos, lípidos y azúcares) proporcionando un sistema que permite tanto la protección como la opción de la entrega simultánea de múltiples mensajeros diferentes, a diversos sitios alejados del lugar de origen vesicular. Sin embargo, el posible papel de las VEs liberadas del hígado durante la cirrosis hepática en el desarrollo de complicaciones pulmonares, incluidas la HPP y el SHP, es desconocido..., Cirrhosis is the final stage of a series of chronic liver diseases, leading to high morbidity and mortality. Furthermore, liver cirrhosis can lead to two specific pulmonary vascular complications: hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PoPH). It is estimated that HPS and PoPH, develop in approximately 30% and 5-10% respectively, of patients with chronic liver disease and cirrhosis. HPS is associated with intrapulmonary vascular dilatations, shunt formation and severe hypoxemia, whereas PoPH is characterised by proliferation, vasoconstriction, vascular remodelling and pulmonary hypertension in the presence of portal hypertension. The lack of suitable animal models is a major limitation for the study of these diseases.Increasing evidence suggests that extracellular vesicles (EVs) may contribute to the development of lung diseases. EVs are a heterogeneous group of cell-derived nanometric membranous structures. They are present in every biological fluid and involved in multiple physiological and pathological processes. The significance of EVs lies in their capacity to transfer information to other cells thereby influencing the recipient cell function. EV-mediated signals can be transmitted by all the different biomolecule categories (protein, nucleic acids, lipids and sugars). The unique package of this information provides both protection and the option of simultaneous delivery of multiple different messengers even to sites remote to the vesicular origin. However, the possible role of EVs released from the liver during liver cirrhosis in the development of pulmonary complications, including HPS and PoPH, is unknown...

Vitamin D (vitD) deficiency is highly prevalent in patients with pulmonary arterial hypertension (PAH). Moreover, PAH-patients with lower levels of vitD have worse prognosis. We hypothesize that recovering optimal levels of vitD in an animal model of PAH previously depleted of vitD improves the hemodynamics, the endothelial dysfunction and the ionic remodeling. Methods: Male Wistar rats were fed a vitD-free diet for five weeks and then received a single dose of Su5416 (20 mg/Kg) and were exposed to vitD-free diet and chronic hypoxia (10% O2) for three weeks to induce PAH. Following this, vitD deficient rats with PAH were housed in room air and randomly divided into two groups: (a) continued on vitD-free diet or (b) received an oral dose of 100,000 IU/Kg of vitD plus standard diet for three weeks. Hemodynamics, pulmonary vascular remodeling, pulmonary arterial contractility, and K+ currents were analyzed. Results: Recovering optimal levels of vitD improved endothelial function, measured by an increase in the endothelium-dependent vasodilator response to acetylcholine. It also increased the activity of TASK-1 potassium channels. However, vitD supplementation did not reduce pulmonary pressure and did not ameliorate pulmonary vascular remodeling and right ventricle hypertrophy. Conclusions: Altogether, these data suggest that in animals with PAH and severe deficit of vitD, restoring vitD levels to an optimal range partially improves some pathophysiological features of PAH., Ministerio de Economía y Competitividad (MINECO), Instituto de Salud Carlos III/ FEDER, Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Introduction: Epidemiological studies suggest a relationship between vitamin D deficiency and cardiovascular and respiratory diseases. However, whether total, bioavailable, and/or free vitamin D levels have a prognostic role in pulmonary arterial hypertension (PAH) is unknown. We aimed to determine total, bioavailable, and free 25-hydroxy-vitamin D (25(OH)vitD) plasma levels and their prognostic value in PAH patients. Methods: In total, 67 samples of plasma from Spanish patients with idiopathic, heritable, or drug-induced PAH were obtained from the Spanish PH Biobank and compared to a cohort of 100 healthy subjects. Clinical parameters were obtained from the Spanish Registry of PAH (REHAP). Results: Seventy percent of PAH patients had severe vitamin D deficiency (total 25(OH)vitD < 10 ng/mL) and secondary hyperparathyroidism. PAH patients with total 25(OH)vitD plasma above the median of this cohort (7.17 ng/mL) had better functional class and higher 6-min walking distance and TAPSE (tricuspid annular plane systolic excursion). The main outcome measure of survival was significantly increased in these patients (age-adjusted hazard ratio: 5.40 (95% confidence interval: 2.88 to 10.12)). Vitamin D-binding protein (DBP) and albumin plasma levels were downregulated in PAH. Bioavailable 25(OH)vitD was decreased in PAH patients compared to the control cohort. Lower levels of bioavailable 25(OH)vitD (<0.91 ng/mL) were associated with more advanced functional class, lower exercise capacity, and higher risk of mortality. Free 25(OH)vitD did not change in PAH; however, lower free 25(OH)vitD (<1.53 pg/mL) values were also associated with high risk of mortality. Conclusions: Vitamin D deficiency is highly prevalent in PAH, and low levels of total 25(OH)vitD were associated with poor prognosis., Ministerio de Economía y Competitividad (MINECO)/FEDER, Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

In addition to playing a role as a structural component of cellular membranes, ceramide is now clearly recognized as a bioactive lipid implicated in a variety of physiological functions. This review aims to provide updated information on the role of ceramide in the regulation of vascular tone. Ceramide may induce vasodilator or vasoconstrictor effects by interacting with several signaling pathways in endothelial and smooth muscle cells. There is a clear, albeit complex, interaction between ceramide and redox signaling. In fact, reactive oxygen species (ROS) activate different ceramide generating pathways and, conversely, ceramide is known to increase ROS production. In recent years, ceramide has emerged as a novel key player in oxygen sensing in vascular cells and mediating vascular responses of crucial physiological relevance such as hypoxic pulmonary vasoconstriction (HPV) or normoxic ductus arteriosus constriction. Likewise, a growing body of evidence over the last years suggests that exaggerated production of vascular ceramide may have detrimental effects in a number of pathological processes including cardiovascular and lung diseases., Ministerio de Economía y Competitividad (MINECO), Instituto de Salud Carlos III (ISCIII)/FEDER, Comunidad de Madrid, Depto. de Farmacología y Toxicología, Fac. de Medicina, TRUE, pub

Los objetivos que se han alcanzado son los siguientes: 1. Teniendo en cuenta los resultados obtenidos durante el curso 2018-19 (además de los resultados obtenidos en el curso 2017-18) los participantes han alcanzado una formación por encima de lo esperado en Farmacología habiendo asistido a una media de 57% del curso en su primer año de participación (cuando lo estipulado en el Plan de Formacion Docente es del 30%). Además, han superado un 42,3% de la materia entre su primer y segundo año con una calificación media de 8,3. 2. Los jóvenes investigadores han realizado una media de 10 horas de prácticas docentes contabilizando aquellas dedicadas a la asistencia a prácticas como oyentes, el ensayo de las prácticas con tutores y la impartición misma de las sesiones de prácticas. El número de horas está muy limitado por el bajo número de horas prácticas en las asignaturas de Farmacología del Dpto. y el elevado número de jóvenes investigadores incorporados al Dpto. 3. Con todo lo anterior, los jóvenes investigadores han alcanzado la formación en competencias docentes y las horas realizadas han sido acreditadas a las respectivas autoridades de sus becas/contratos. Su participación en la docencia práctica les permitirá en el futuro solicitar un certificado de actividades docentes emitido por las autoridades académicas de la Facultad de Medicina que avalaran su experiencia docente en solicitudes de acreditación a las diferentes figuras de profesor ante la ANECA. Además, el Dpto. de Farmacología y Toxicología ha emitido informes detallados de Aptitud Docente en Farmacología reflejando su participación en el Plan de Formación Docente del Dpto. que podrán ser consideradas en solicitudes a puestos docentes en el futuro.

Background: We hypothesized that treatment with quercetin could result in improved hemodynamics, lung inflammatory parameters and mortality in a rat model of hemorrhagic shock. Methods: Rats were anesthetized (80 mg/kg ketamine plus 8 mg/kg xylazine i.p.). The protocol included laparotomy for 15 min (trauma), hemorrhagic shock (blood withdrawal to reduce the mean arterial pressure to 35 mmHg) for 75 min and resuscitation by re-infusion of all the shed blood plus lactate Ringer for 90 min. Intravenous quercetin (50 mg/kg) or vehicle were administered during resuscitation. Results: There was a trend for increased survival 84.6% (11/13) in the treated group vs. the shock group 68.4% (13/19, p > 0.05 Kaplan–Meier). Quercetin fully prevented the development of lung edema. The activity of aSMase was increased in the shock group compared to the sham group and the quercetin prevented this effect. However, other inflammatory markers such as myeloperoxidase activity, interleukin-6 in plasma or bronchoalveolar fluid were similar in the sham and shock groups. We found no bacterial DNA in plasma in these animals. Conclusions: Quercetin partially prevented the changes in blood pressure and lung injury in shock associated to hemorrhage and reperfusion., Ministerio de Economía y Competitividad (MINECO), Instituto de Salud Carlos III (ISCIII), Fundación Mutua Madrileña, Depto. de Farmacología y Toxicología, Depto. de Medicina, Fac. de Medicina, TRUE, pub