Eficácia e segurança de Riociguate comparado ao placebo e a medicamentos disponíveis no sus para tratamento de hipertensão pulmonar tromboembólica crônica: revisão rápida de evidências / Effectiveness and safety of Riociguate compared to placebo and drugs available in brazilian public health for treatment of chronic thromboembolic pulmonary hypertension: rapid response review of evidence

Tecnologia: Riociguate e outros medicamentos de controle da hipertensão pulmonar. Indicação: Tratamento de Hipertensão Pulmonar Tomboembólica Crônica (HPTEC). Pergunta: Há superioridade em eficácia e segurança do riociguate, comparado a medicamentos disponíveis no SUS, no tratamento de HPTEC inoperável ou operada com hipertensão pulmonar residual? Métodos: Revisão rápida de evidências (overview) de revisões sistemáticas, com levantamento bibliográfico realizado na base de dados PUBMED, utilizando estratégia estruturada de busca. A qualidade metodológica das revisões sistemáticas foi avaliada com AMSTAR-2 (Assessing the Methodological Quality of Systematic Reviews). Resultados: Foram selecionadas 4 e incluídas 2 revisões sistemáticas. Conclusão: Comparado ao placebo, em tratamento de curto prazo de HPTEC, riociguate melhora a tolerância ao exercício, aumenta a chance de melhora da classificação funcional e tem similar risco de eventos adversos sérios, porém não reduz a mortalidade. Treprostinil tem efeitos similares a riociguate. Entretanto, ambrisentana, bosentana, macitentana ou sildenafila não diferem do placebo no tratamento de HPTEC

Technology: Riociguat and other drugs to control pulmonary hypertension. Indication: Treatment of chronic thromboembolic pulmonary hypertension (CTEPH). Question: Is riociguat more effective and safe than other drugs available in the Brazilian Public Health System for the treatment of inoperable or recurrent CTEPH? Methods: Rapid review of evidence (overview) from systematic reviews, with a bibliographic search in the PUBMED database, using a structured strategy. The methodological quality of systematic reviews was assessed with AMSTAR-2 (Methodological Quality Assessment of Systematic Reviews). Results: Four systematic reviews were selected and two included in this study. Conclusion: Compared to placebo, in the short-term treatment of CTEPH, riociguat improves exercise tolerance, increases the chance of improving functional classification, and has a similar risk of serious adverse events, but does not reduce mortality. Treprostinil has similar effects to riociguat. However, ambrisentan, bosentan, macitentan or sildenafil do not differ from placebo in the treatment of CTEPH

From Escherichia coli heat-stable enterotoxin to mammalian endogenous guanylin hormones

The isolation of heat-stable enterotoxin (STa) from Escherichia coli and cholera toxin from Vibrio cholerae has increased our knowledge of specific mechanisms of action that could be used as pharmacological tools to understand the guanylyl cyclase-C and the adenylyl cyclase enzymatic systems. These discoveries have also been instrumental in increasing our understanding of the basic mechanisms that control the electrolyte and water balance in the gut, kidney, and urinary tracts under normal conditions and in disease. Herein, we review the evolution of genes of the guanylin family and STa genes from bacteria to fish and mammals. We also describe new developments and perspectives regarding these novel bacterial compounds and peptide hormones that act in electrolyte and water balance. The available data point toward new therapeutic perspectives for pathological features such as functional gastrointestinal disorders associated with constipation, colorectal cancer, cystic fibrosis, asthma, hypertension, gastrointestinal barrier function damage associated with enteropathy, enteric infection, malnutrition, satiety, food preferences, obesity, metabolic syndrome, and effects on behavior and brain disorders such as attention deficit, hyperactivity disorder, and schizophrenia.

Selective mastoporan inhibition of muscarinic activation of bovine tracheal smooth muscle

Muscarinic activation of bovine tracheal smooth muscle (BTSM) leading to smooth muscle contraction involves the generation of two cGMP signals (20 and 60 s), being 20s peak associated with soluble (sGC) and the second (60s) to membrane-bound Natriuretic Peptide- receptor-Guanylylcy clases (NPR-GC). In this study, we showed that pre-incubation of isolated BTSM strips with mastoparan and superactive mastoparan (mastoparan 7) decreased significantly the muscarinic dependent contractile smooth muscle responses in dose-dependent and non-competitive manner. Moreover, mastoparan (50 nM) inhibited completely the BTSM-muscarinic contractile responses and affected dramatically the carbachol-dependent cGMP signals being the first cGMP signal inhibited in a 63 ± 5%, whereas the second signal disappeared. Mastoparan inhibition of muscarinic activation is specific since other spasmogens as serotonin and histamine fully contracted these BTSM strips under mastoparan treatment. Cyclic GMP levels were evaluated by exposing BTSM strips to activators of NO-sensitive sGC as Sodium Nitroprussiate (SNP) and Natriuretic Peptides as CNP-53 for membrane-bound NPR-GC. Thus, SNP and CNP increased in a binary way, in more than 20 fold cGMP levels at 30-40 s being both increments inhibited by mastoparan. Furthermore, the Gi/o-protein involvement on mastoparan inhibition of cGMP elevations induced by CNP and SNP is suggested by Pertussis toxin pre-treatment, which reversed mastoparan effects. These results indicate that muscarinic signal transduction cascades leading to airway smooth muscle contractions involved two different guanylyl cyclases being both regulated by mastoparan-sensitive G-proteins. ANP, Natriuretic Peptide type A; ASM, Airway Smooth Muscle; BTSM, Bovine Tracheal Smooth Muscle; CNP-53, Natriuretic Peptide type C-53; GPCR, G-Protein Coupled Receptor; Gq16, Heterotrimeric G protein subtype 16; Gi/o, Heterotrimeric G protein subtype...

La activación muscarínica del músculo liso de las vías aéreasrelacionada a la contracción de dicho músculo liso esta asociada a la generación de dos señales de GMPc (20 y 60 s), siendo la señal de los 20s relacionado a la activación de la guanililciclasa soluble mientras que el pico de los 60s a la guanililciclasa unida membranas y sensible a péptidos natriuréticos (NPR-GC). En este trabajo, nosotros mostramos que la pre-incubación de fragmentos del músculo liso traqueal de bovino (BTSM) con mastoparan y su análogo superactivo (mastoparan 7), en una forma dosis dependiente, son capaces de disminuir de manera significativa la actividad contráctil dependiente de agentes muscarinicos. Adicionalmente, mastoparan (50 nM) inhibió completamente la respuesta contráctil muscarinica del BTSM y afectó dramáticamente los picos de GMPc asociados a la activación muscarinica siendola primera señal inhibida en un 63 ± 5%, mientras que la segunda señal desapareció completamente. Esta inhibición del mastoparan de la activación muscarínica es especifica ya que otros espamogenos como la serotonina y la histamina fueron capaces de inducir respuestas máximas en presencia del mastoparan y su análogos. Este efecto del mastoparan sobre los niveles del GMPc fue evaluado en presencia de otros agentes generadores de este segundo mensajero como son el nitroprusiato de sodio (SNP) que activa la guanililciclasa soluble sensible a NO y los péptidos natriureticos como el CNP-53 (CNP) activador de la NPR-GC asociada a membranas plasmáticas. Tanto, el SNP como el CNP aumentaronen mas de 50 veces los niveles de GMPc a los 30-40 s en forma bifasica, siendo estos incrementos inhibidos de manera significativa por el mastoparan. Ademas, se sugiere la participación de proteínas Gi/o en los efectos inhibitoriosdel mastoparan, porque la Toxina pertussis revertió los efectos inhibitorios. Estos resultados indican que la cascada de activación muscarinica que conduce...