Person:
Leite Fernandes, Vitor Samuel

First Name

Vitor Samuel

Last Name

Leite Fernandes

URI

https://hdl.handle.net/20.500.14352/77683

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Farmacia

Department

Fisiología

Area

Fisiología

Identifiers

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Now showing 1 - 10 of 16

Novel mechanism of hydrogen sulfide-induced guinea pig urinary bladder smooth muscle contraction: role of BK channels and cholinergic neurotransmission
(American journal of physiology. Cell physiology, 2015) Leite Fernandes, Vitor Samuel; Xin, Wenkuan; Petkov, Georgi V.
Hydrogen sulfide (H2S) is a key signaling molecule regulating important physiological processes, including smooth muscle function. However, the mechanisms underlying H2S-induced detrusor smooth muscle (DSM) contractions are not well understood. This study investigates the cellular and tissue mechanisms by which H2S regulates DSM contractility, excitatory neurotransmission, and large-conductance voltage- and Ca2+-activated K+ (BK) channels in freshly isolated guinea pig DSM. We used a multidisciplinary experimental approach including isometric DSM tension recordings, colorimetric ACh measurement, Ca2+ imaging, and patch-clamp electrophysiology. In isolated DSM strips, the novel slow release H2S donor, P-(4-methoxyphenyl)-p-4-morpholinylphosphinodithioic acid morpholine salt (GYY4137), significantly increased the spontaneous phasic and nerve-evoked DSM contractions. The blockade of neuronal voltage-gated Na+ channels or muscarinic ACh receptors with tetrodotoxin or atropine, respectively, reduced the stimulatory effect of GYY4137 on DSM contractility. GYY4137 increased ACh release from bladder nerves, which was inhibited upon blockade of L-type voltage-gated Ca2+ channels with nifedipine. Furthermore, GYY4137 increased the amplitude of the Ca2+ transients and basal Ca2+ levels in isolated DSM strips. GYY4137 reduced the DSM relaxation induced by the BK channel opener, NS11021. In freshly isolated DSM cells, GYY4137 decreased the amplitude and frequency of transient BK currents recorded in a perforated whole cell configuration and reduced the single BK channel open probability measured in excised inside-out patches. GYY4137 inhibited spontaneous transient hyperpolarizations and depolarized the DSM cell membrane potential. Our results reveal the novel findings that H2S increases spontaneous phasic and nerve-evoked DSM contractions by activating ACh release from bladder nerves in combination with a direct inhibition of DSM BK channels.
Role of Calcitonin Gene-Related Peptide in Inhibitory Neurotransmission to the Pig Bladder Neck
(2011) Martínez-Sáenz, Ana ; Recio Visedo, María Paz; Orensanz, Luis M. ; Leite Fernandes, Vitor Samuel; Martínez Sainz, María Del Pilar; Bustamante, Salvador ; Carballido, Joaquín ; García-Sacristán, Albino ; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo Vicente
Purpose: We studied the role of calcitonin gene-related peptide in nonadrenergic, noncholinergic neurotransmission to the pig bladder neck. Materials and Methods: We used immunohistochemical techniques to determine the distribution of calcitonin gene-related peptide immunoreactive fibers as well as organ baths for isometric force recording. We investigated relaxation due to endogenously released or exogenously applied calcitonin gene-related peptide in urothelium denuded phenylephrine precontracted strips treated with guanethidine, atropine and NG-nitro-L-arginine to block noradrenergic neurotransmission, muscarinic receptors and nitric oxide synthase, respectively. Results: Rich calcitonin gene-related peptide immunoreactive innervation was found penetrating through the adventitia and distributed in the suburothelial and muscle layers. Numerous, variable size, varicose calcitonin gene-related peptide immunopositive terminals were seen close below the urothelium. In the muscle layer calcitonin gene-related peptide immunopositive nerves usually appeared as varicose terminals running along muscle fibers. Electrical field stimulation (2 to 16 Hz) and exogenous calcitonin gene-related peptide (0.1 nM to 0.3 μM) evoked frequency and concentration dependent relaxation, respectively. Nerve responses were potentiated by capsaicin, decreased by calcitonin gene-related peptide (8–37) and abolished by tetrodotoxin, capsaicin sensitive primary afferent blockers, calcitonin gene-related peptide receptors and neuronal voltage gated Na+ channels. Calcitonin gene-related peptide-induced relaxation was potentiated by the neuronal voltage gated Ca2+ channels blocker ω-conotoxin-GVIA and decreased by calcitonin gene-related peptide (8–37). Calcitonin gene-related peptide relaxation was not modified by blockade of endopeptidases, nitric oxide synthase, guanylyl cyclase and cyclooxygenase. Conclusions: Results suggest that calcitonin gene-related peptide is involved in the nonadrenergic, noncholinergic inhibitory neurotransmission of the pig bladder neck, producing relaxation through neuronal and muscle calcitonin gene-related peptide receptors. Nitric oxide/cyclic guanosine monophosphate and cyclooxygenase pathways do not seem to be involved in such responses.
Cardiac System during the Aging Process
(Aging and disease, 2023) Fernandes Ribeiro, Ana Sofía; Egea Zerolo, Blanca; Lopez-Espuela, Fidel; Sanchez, Raul; Leite Fernandes, Vitor Samuel
The aging process is accompanied by a continuous decline of the cardiac system, disrupting the homeostatic regulation of cells, organs, and systems. Aging increases the prevalence of cardiovascular diseases, thus heart failure and mortality. Understanding the cardiac aging process is of pivotal importance once it allows us to design strategies to prevent age-related cardiac events and increasing the quality of live in the elderly. In this review we provide an overview of the cardiac aging process focus on the following topics: cardiac structural and functional modifications; cellular mechanisms of cardiac dysfunction in the aging; genetics and epigenetics in the development of cardiac diseases; and aging heart and response to the exercise.
Neuronal and non-neuronal bradykinin receptors are involved in the contraction and/or relaxation to the pig bladder neck smooth muscle
(Neurourology and urodynamics, 2013) Ribeiro, Ana Sofía Fernandes; Leite Fernandes, Vitor Samuel; Martínez Sainz, María Del Pilar; Martínez-Sáenz, Ana; Pazos Rodríguez, María Ruth; Orensanz Muñoz, Luis Miguel; Recio Visedo, María Paz; Bustamante Alarma, Salvador; Carballido Rodríguez, Joaquín; García Sacristán, Albino; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo Vicente
Aims: The current study investigates the role played by bradykinin (BK) receptors in the contractility to the pig bladder neck smooth muscle. Methods: Bladder neck strips were mounted in myographs for isometric force recordings and BK receptors expression was also determined by immunohistochemistry. Results: B2 receptor expression was observed in the muscular layer and urothelium whereas B1 expression was consistent detected in urothelium. A strong B2 immunoreactivity was also observed within nerve fibers among smooth muscle bundles. On urothelium-denuded preparations basal tone, BK induced concentration-dependent contractions which were reduced in urothelium-intact samples, by extracellular Ca(2+) removal and by blockade of B2 receptors and voltage-gated Ca(2+) (VOC) and non-VOC channels, and increased by cyclooxygenase (COX) inhibition. On phenylephrine-precontracted denuded strips, under non-adrenergic non-cholinergic (NANC) conditions, electrical field stimulation-elicited frequency-dependent relaxations which were reduced by B2 receptor blockade. In urothelium-intact samples, the B1 receptor agonist kallidin promoted concentration-dependent relaxations which were reduced by blockade of B1 receptors, COX, COX-1 and large-conductance Ca(2+) -activated K(+) (BKCa ) channels and abolished in urothelium-denuded samples and in K(+) -enriched physiological saline solution-precontracted strips. Conclusions: These results suggest that BK produces contraction of pig bladder neck via smooth muscle B2 receptors coupled to extracellular Ca(2+) entry via VOC and non-VOC channels with a minor role for intracellular Ca(2+) mobilization. Facilitatory neuronal B2 receptors modulating NANC inhibitory neurotransmission and urothelial B1 receptors producing relaxation via the COX-1 pathway and BKCa channel opening are also demonstrated.
Project number: 407
Autoevaluación, Coevaluación y el uso de las TIC como enfoque innovador en las prácticas de Fisiopatología y su efecto en el proceso de enseñanza-aprendizaje del alumno
(2023) Leite Fernandes, Vitor Samuel; Agis Torres, Ángel; Benedito Castellote, Sara; Climent Flórez, Belén; Contreras Jiménez, Cristina; García Sacristán, Albino; Gómez del Val, Alfonso; Hernández Rodríguez, Medardo Vicente; Hernández Martín, Marina; López-Oliva Muñoz, María Elvira; Merino Martín, José Joaquín; Montenegro Álvarez De Tejera, María Pilar; Muñoz Picos, Mercedes; Navarro Dorado, Jorge; Pascual Gómez, Natalia Fernanda; Perales Calvo, Manuel; Prieto Ocejo, Dolores; Puente Maya, Francisco Jesus; Raposo González, Rafaela; Recio Visedo, María Paz; Rivera De Los Arcos, Luis; Sánchez Pina, Ana Alejandra
En las últimas décadas, la educación universitaria ha evolucionado hacia un enfoque constructivista en consonancia con las recomendaciones del Espacio Europeo de Educación Superior (EEES). En este paradigma, los estudiantes asumen un papel activo en el proceso de enseñanza-aprendizaje, mientras los profesores actúan como facilitadores. Las metodologías constructivistas fomentan el desarrollo tanto individual como grupal de competencias específicas y genéricas, al tiempo que permiten la inclusión de agentes de evaluación formativa para estimular la crítica y la autocrítica del alumno en su desempeño. En este contexto, surge la necesidad de aplicar el constructivismo a la evaluación, involucrando al estudiante en su propio proceso de evaluación. La autoevaluación y la coevaluación emergen como alternativas concretas para lograrlo. La autoevaluación implica que el estudiante analice y valore de manera sistemática su trabajo durante el proceso de aprendizaje para mejorar resultados y fomentar la autocrítica. Por otro lado, la coevaluación es una evaluación entre compañeros que permite valorar la implicación y actitud de los miembros del grupo, estimulando el aprendizaje colectivo. Las Tecnologías de la Información y Comunicación (TIC) juegan un papel importante en la educación y en la evaluación de los alumnos, diferenciándose de las prácticas tradicionales. La implementación de TIC no solo desarrolla habilidades en el proceso enseñanza-aprendizaje, sino también favorece la autoevaluación y la coevaluación. Con base en este enfoque, se presenta un proyecto de innovación docente en la asignatura de Fisiopatología para estudiantes de Farmacia. Los alumnos crearán videos sobre temas específicos de la práctica y se evaluarán a sí mismos y a sus compañeros utilizando la herramienta App Plickers. Sin embargo, aún no existe una metodología claramente definida para la implementación de estrategias constructivistas y uso de TIC en Fisiopatología, destacando la importancia y relevancia de este proyecto.
The bitter taste receptor (TAS2R) agonist denatonium promotes a strong relaxation of rat corpus cavernosum
(Biochemical Pharmacology, 2023) Navarro Dorado, Jorge; Climent Flórez, Belén; López-Oliva Muñoz, María Elvira; Martínez Sainz, María Del Pilar; Hernández Martín, Marina; Agis Torres, Ángel; Recio Visedo, María Paz; Barahona Gomáriz, María Victoria; Benedito Castellote, Sara; Leite Fernandes, Vitor Samuel; Hernández Rodríguez, Medardo Vicente
Bitter taste receptors (TAS2R) are found in numerous extra-oral tissues, including smooth muscle (SM) cells in both vascular and visceral tissues. Upon activation, TAS2R stimulate the relaxation of the SM. Nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway is involved in penile erection, and type 5 phosphodiesterase (PDE5) inhibitors, a cGMP-specific hydrolase are used as first-line treatments for erectile dysfunction (ED). Nevertheless, PDE5 inhibitors are ineffective in a considerable number of patients, prompting research into alternative pharmacological targets for ED. Since TAS2R agonists regulate SM contractility, this study investigates the role of TAS2Rs in rat corpus cavernosum (CC). We performed immunohistochemistry to detect TAS2R10, isometric force recordings for TAS2R agonists denatonium and chloroquine, the slow-release H2S donor GYY 4137, the NO donor SNAP, the β-adrenoceptor agonist isoproterenol and electrical field stimulation (EFS), as well as measurement of endogenous hydrogen sulfide (H2S) production. The immunofluorescence staining indicated that TAS2R10 was broadly expressed in the CC SM and to some extent in the nerve fibers. Denatonium, chloroquine, SNAP, and isoproterenol cause potent dose-dependent SM relaxations. H2S production was decreased by NO and H2S synthase inhibitors, while it was enhanced by denatonium. In addition, denatonium increased the relaxations induced by GYY 4137 and SNAP but failed to modify EFS- and isoproterenol-induced responses. These results suggest neuronal and SM TAS2R10 expression in the rat CC, where denatonium induces a strong SM relaxation per se and promotes the H2S- and NO-mediated inhibitory gaseous neurotransmission. Thus, TAS2R10 might represent a valuable therapeutic target in ED.
Endogenous Hydrogen Sulfide has a Powerful Role in Inhibitory Neurotransmission to the Pig Bladder Neck
(Journal of Urology, 2013) Leite Fernandes, Vitor Samuel; Ribeiro, Ana S.F.; Martínez, María Pilar; Orensanz, Luis M.; Barahona Gomáriz, María Victoria; Martínez-Sáenz, Ana; Recio Visedo, María Paz; Benedito Castellote, Sara; Bustamante, Salvador; Carballido, Joaquín; García Sacristán, Albino; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo Vicente
Purpose: We investigated the possible involvement of H2S in nitric oxide independent inhibitory neurotransmission to the pig bladder neck. Materials and methods: We used immunohistochemistry to determine the expression of the H2S synthesis enzymes cystathionine γ-lyase and cystathionine β-synthase. We also used electrical field stimulation and myographs for isometric force recordings to study relaxation in response to endogenously released or exogenously applied H2S in urothelium denuded, phenylephrine precontracted bladder neck strips under noradrenergic, noncholinergic, nonnitrergic conditions. Results: Cystathionine γ-lyase and cystathionine β-synthase expression was observed in nerve fibers in the smooth muscle layer. Cystathionine γ-lyase and cystathionine β-synthase immunoreactive fibers were also identified around the small arteries supplying the bladder neck. Electrical field stimulation (2 to 16 Hz) evoked frequency dependent relaxation, which was decreased by DL-propargylglycine and abolished by tetrodotoxin (blockers of cystathionine γ-lyase and neuronal voltage gated Na(+) channels, respectively). The cystathionine β-synthase inhibitor O-(carboxymethyl)hydroxylamine did not change nerve mediated responses. The H2S donor GYY4137 (0.1 nM to 10 μM) induced potent, concentration dependent relaxation, which was not modified by neuronal voltage gated Na(+) channels, or cystathionine γ-lyase or cystathionine β-synthase blockade. Conclusions: Results suggest that endogenous H2S synthesized by cystathionine γ-lyase and released from intramural nerves acts as a powerful signaling molecule in nitric oxide independent inhibitory transmission to the pig bladder neck.
In vitro inhibition of phosphodiesterase type 4 enhances rat corpus cavernosum nerve-mediated relaxation induced by gasotransmitters
(Life Sciences, 2022) Leite Fernandes, Vitor Samuel; López-Oliva Muñoz, María Elvira; Martínez Sainz, María Del Pilar; Agis Torres, Ángel; Recio Visedo, María Paz; Navarro Dorado, Jorge; Barahona Gomáriz, María Victoria; Benedito Castellote, Sara; Prieto Ocejo, Dolores; Climent Flórez, Belén; Hernández Rodríguez, Medardo Vicente
Aims: Nitric oxide (NO) and hydrogen sulfide (H2S) are involved in nerve-mediated corpus cavernosum (CC) relaxation. Expression of phosphodiesterase type 5 (PDE5) and type 4 (PDE4), cyclic guanosine monophosphate (cGMP)- and cyclic adenosine monophosphate (cAMP)-specific, respectively, has been described and PDE5- and PDE4-inhibitors induce cavernous smooth muscle relaxation. Whereas the NO/cGMP signaling pathway is well established in penile erection, the cAMP-mediated mechanism is not fully elucidated. The aim of this study is to investigate the localization and the functional significance of PDE4 in rat CC tone regulation. Main methods: We performed immunohistochemistry for the detection of the PDE4A isoenzyme. Isometric tension recordings for roflumilast and tadalafil, PDE4 and PDE5 inhibitors, respectively, electrical field stimulation (EFS) and β-adrenoceptor agonist isoproterenol and endogenous H2S production measurement. Key findings: A marked PDE4A expression was detected mainly localized in the nerve cells of the cavernous smooth muscle. Furthermore, roflumilast and tadalafil exhibited strong corpus cavernous relaxations. Endoge-nous H2S production was decreased by NO and H2S synthase inhibitors and increased by roflumilast. Isopro-terenol- and EFS-induced relaxations were increased by roflumilast. Significance: These results indicate that PDE4A is mainly expressed within the nerves cells of the rat CC, where roflumilast induces a potent corpus cavernous relaxation per se and potentiates the response induced by β-adrenoceptor activation. The fact that roflumilast enhances H2S production, as well as EFS-elicited responses suggests that PDE4 inhibitors modulate, in a positive feedback fashion, nerve-mediated relaxation induced by gasotransmitters, thus indicating a key role for neuronal PDE4 in penile erection.
Stop Hipertensión con APS/UCM I
(2023) López-Oliva Muñoz, María Elvira; Sánchez Pina, Ana Alejandra; Hernández Martín, Marina; Rivera De Los Arcos, Luis; López-Calderón Barreda, Asunción; Paredes Royano, Sergio Damián; Vicente Torres, María Ángeles; Heras Jiménez, Natalia De Las; Benedito Castellote, Sara; Prieto Ocejo, Dolores; Issa García, Jousef Ángel; García Donaire, José Antonio; Abad Cardiel, María; Martell Claros, Nieves; Gómez Garre, María Dulce Nombre; Azcutia Criado, Verónica; Contreras Jiménez, Cristina; Redondo Castillejo, Rocío; Hurtado Carneiro, Verónica; Rodrigues Díez, Raquel; Cachofeiro Ramos, María Victoria; Montenegro Álvarez De Tejera, María Pilar; Das Chagas Vasconcelos de Sousa Neto, Francisco; Gómez del Val, Alfonso; Bravo San Pedro, José Manuel; Colino Galián, Belén; Fernández García, Maria José; Flóres Alcázar, Rocío; Rodríguez Ramiro, Ildefonso; Agis Torres, Ángel; García-Baro López, José Antonio; Gredilla Díaz, Ricardo; Hernández Rodríguez, Medardo Vicente; Leite Fernandes, Vitor Samuel; Lozano Estevan, María Del Carmen; Martín Velasco, Ana Isabel; Martínez Martínez, Ernesto; Moreno Rupérez, Álvaro; Muñoz Picos, Mercedes; Navarro Dorado, Jorge; Nebot Valenzuela, Elena; Pascual Gómez, Natalia Fernanda; Perales Calvo, Manuel; Priego Cuadra, Teresa; Puente Maya, Francisco Jesús; Raposo González, Rafaela; Recio Visedo, María Paz; Sánchez-Aguilera López, Alberto; Sancho González, María; Segovia Camargo, Gregorio; Soriano Amador, Cristina
El Proyecto Stop Hipertensión con ApS/UCM pretende aportar nuestro granito de arena a la lucha contra la hipertensión arterial (HTA), utilizando una herramienta educativa de aprendizaje en servicio (ApS), que permita a los estudiantes de los Grados en ciencias de la salud de la UCM aprender a la vez que realizan un servicio público. La hipertensión arterial (HTA) es un problema de salud pública y un importante factor de riesgo de padecer enfermedades cardiovasculares (ECV). Su diagnóstico está determinado por la medida de la presión arterial (PA) por lo que es de extrema importancia asegurar una medida fiable y válida. La automedida de la PA (AMPA) consiste en la medida de la PA por el propio paciente o un familiar, habitualmente en su domicilio, y es una herramienta útil para el diagnóstico y control de la HTA. Pero ¿sabemos medirnos de forma correcta la PA? ¿Usamos bien los tensiómetros? ¿Sabemos interpretar los registros de la PA y cuándo consultar al médico? Realizar AMPA correctamente no es fácil y exige un esfuerzo extraordinario de recursos humanos y económicos por parte de los profesionales de Atención Primaria. Por ello son necesarias nuevas estrategias para capacitar a la población en AMPA. Con este Proyecto nos proponemos luchar contra la HTA a través de la metodología educativa de aprendizaje-servicio que combina objetivos académicos con el servicio comunitario. El alumnado de los grados de Ciencias de la Salud de la UCM forman a la población en la correcta AMPA, asesorándoles sobre el uso correcto de los tensiómetros, enseñándoles a interpretar los resultados y alertándoles de cuándo acudir al médico. En el curso 2022-2023, el servicio público se ha dirigido principalmente al colectivo de mayores por ser especialmente vulnerables a padecer ECV en los Ayuntamientos de Coslada, Alcobendas y Alcorcón, y en las residencias Afanias y Neurovida, y a la población general que acuda a la Facultad durante la Semana de la Ciencia CAM/UCM 2022, a la Feria de la Salud de Coslada y a la campaña contra la HTA de la UCM junto con el Servicio de Medicina del Trabajo. Hemos demostrado que este proyecto es una herramienta rentable y efectiva en la lucha contra la HTA, vinculando la salud pública, los recursos de los ayuntamientos y la universidad. Se cubre así una necesidad y servicio social que podría salvar muchas vidas con recursos de bajo costo, cumpliendo con los objetivos del desarrollo sostenible y con los objetivos de la Sociedad Española de Hipertensión (SEH-LELHA) y de la estrategia HEARTS de la OPS/OMS. Los estudiantes se dan cuenta de la realidad de la Salud pública al tener contacto directo con la población, realizando un servicio a la sociedad, y desarrollándose profesionalmente. Agrademos su colaboración a: Los ayuntamientos de Coslada, Alcorcón y Alcobendas de Madrid. Las residencias de mayores Afanias y Neurovida. Las Sociedades científicas SEH-LELHA, SECF y SEAPEC. El Dr. Orduñez, lider de la estrategia HEARTS PAHO/WHO Los colegios profesionales COFM y CODEM. Las empresas River International S.L. (Beurer) and Peroxfarma S.L. (Omrom)
Bladder Dysfunction in an Obese Zucker Rat: The Role of TRPA1 Channels, Oxidative Stress, and Hydrogen Sulfide
(2019) Blaha, Igor; López-Oliva Muñoz, María Elvira; Martínez Sainz, María Del Pilar; Recio Visedo, María Paz; Agis Torres, Ángel; Martínez Gómez, Ana Cristina; Benedito Castellote, Sara; García Sacristán, Albino; Leite Fernandes, Vitor Samuel; Prieto Ocejo, Dolores; Hernández Rodríguez, Medardo Vicente
Purpose: This study investigates whether functionality and/or expression changes of transient receptor potential vanilloid 1 (TRPV1) and transient receptor potential ankyrin 1 (TRPA1) channels, oxidative stress, and hydrogen sulfide (H2S) are involved in the bladder dysfunction from an insulin-resistant obese Zucker rat (OZR). Materials and methods: Detrusor smooth muscle (DSM) samples from the OZR and their respective controls, a lean Zucker rat (LZR), were processed for immunohistochemistry for studying the expression of TRPA1 and TRPV1 and the H2S synthase cystathionine beta-synthase (CBS) and cysthathionine-γ-lyase (CSE). Isometric force recordings to assess the effects of TRPA1 agonists and antagonists on DSM contractility and measurement of oxidative stress and H2S production were also performed. Results: Neuronal TRPA1 expression was increased in the OZR bladder. Electrical field stimulation- (EFS-) elicited contraction was reduced in the OZR bladder. In both LZR and OZR, TRPA1 activation failed to modify DSM basal tension but enhanced EFS contraction; this response is inhibited by the TRPA1 blockade. In the OZR bladder, reactive oxygen species, malondialdehyde, and protein carbonyl contents were increased and antioxidant enzyme activities (superoxide dismutase, catalase, GR, and GPx) were diminished. CSE expression and CSE-generated H2S production were also reduced in the OZR. Both TRPV1 and CBS expressions were not changed in the OZR. Conclusions: These results suggest that an increased expression and functionality of TRPA1, an augmented oxidative stress, and a downregulation of the CSE/H2S pathway are involved in the impairment of nerve-evoked DSM contraction from the OZR.