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2.
Rev. Asoc. Méd. Argent ; 136(1): 14-18, mar. 2023. tab
Artigo em Espanhol | LILACS | ID: biblio-1553747

RESUMO

El objetivo de este artículo es comparar las propiedades químicas y farmacológicas del telmisartán y el losartán, y su metabolito activo EXP3174, con el fin de entender por qué el telmisartán es efectivo en pacientes hospitalizados con Covid-19 mientras que el losartán no lo es. Se llevó a cabo una revisión bibliográfica exhaustiva de las propiedades químicas, farmacocinéticas y farmacodinámicas de ambos fármacos y se destacaron las diferencias más importantes que podrían estar relacionadas con su efectividad en pacientes con Covid-19. Se concluyó que las propiedades farmacológicas del telmisartán, como su mayor afinidad por el receptor AT1, su duración de acción prolongada y su capacidad para modular la inflamación podrían explicar su efectividad en pacientes con Covid-19. Por otro lado, las propiedades farmacológicas del losartán, como su menor afinidad por el receptor AT1 y su rápido metabolismo, pueden limitar su efectividad en pacientes con Covid-19. Estos resultados resaltan la importancia de comprender las propiedades químicas y farmacológicas de los medicamentos para identificar posibles candidatos terapéuticos efectivos en el tratamiento de Covid-19. (AU)


The objective of this article is to compare the chemical and pharmacological properties of telmisartan and losartan and their active metabolite EXP3174 to understand why telmisartan is effective in hospitalized patients with COVID-19 while losartan is not. A comprehensive literature review of the chemical, pharmacokinetic and pharmacodynamic properties of both drugs was done to highlight the most important differences that may be related to their efficacy in patients with COVID-19. It was concluded that the pharmacological properties of telmisartan, such as its higher affinity for the AT1 receptor, its long duration of action and its ability to modulate inflammation, could explain its efficacy in patients with COVID-19. On the other hand, the pharmacological properties of losartan, such as its lower affinity for the AT1 receptor and its rapid metabolism, may limit its efficacy in patients with COVID-19. These results highlight the importance of understanding the chemical and pharmacological properties of drugs to identify potential effective therapeutic candidates for the treatment of COVID-19. (AU)


Assuntos
Losartan/farmacologia , Telmisartan/farmacologia , Tratamento Farmacológico da COVID-19 , Ensaios Clínicos Controlados como Assunto , Losartan/química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Telmisartan/química , Hospitalização
3.
Front Pharmacol ; 12: 603736, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854432

RESUMO

COVID-19 pandemic demands a swift response to find therapeutic tools that effectively reduce morbidity and mortality. Despite initial fears, evidence from retrospective observational studies supports the inhibition of the renin-angiotensin system as an emerging pathway to delay or moderate angiotensin II-driven lung inflammation. This has triggered several prospective clinical trials. In this commentary we provide an overview and analysis of current ongoing clinical trials aimed at evaluating the therapeutic efficacy of angiotensin receptor blocker (ARB) use in COVID-19. The relevance of the results of these trials will have to be interpreted depending on the stage and severity of the disease and in light of the start time of their prescription related to the time of diagnosis of COVID-19 as well as the administered doses.

4.
Drug Dev Res ; 81(7): 768-770, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32356926

RESUMO

In late 2019, a new coronavirus emerged in Wuhan Province, China, causing lung complications similar to those produced by the SARS coronavirus in the 2002-2003 epidemic. This new disease was named COVID-19 and the causative virus SARS-CoV-2. The SARS-CoV-2 virus enters the airway and binds, by means of the S protein on its surface to the membrane protein ACE2 in type 2 alveolar cells. The S protein-ACE2 complex is internalized by endocytosis leading to a partial decrease or total loss of the enzymatic function ACE2 in the alveolar cells and in turn increasing the tissue concentration of pro-inflammatory angiotensin II by decreasing its degradation and reducing the concentration of its physiological antagonist angiotensin 1-7. High levels of angiotensin II on the lung interstitium can promote apoptosis initiating an inflammatory process with release of proinflammatory cytokines, establishing a self-powered cascade, leading eventually to ARDS. Recently, Gurwitz proposed the tentative use of agents such as losartan and telmisartan as alternative options for treating COVID-19 patients prior to development of ARDS. In this commentary article, the authors make the case for the election of telmisartan as such alternative on the basis of its pharmacokinetic and pharmacodynamic properties and present an open-label randomized phase II clinical trial for the evaluation of telmisartan in COVID-19 patients (NCT04355936).


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Tratamento Farmacológico da COVID-19 , SARS-CoV-2/fisiologia , Telmisartan/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , Ensaios Clínicos Fase II como Assunto , Humanos , Pulmão/metabolismo , Pulmão/virologia , Pandemias , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Telmisartan/farmacologia , Internalização do Vírus/efeitos dos fármacos
5.
J Pharmacol Exp Ther ; 357(1): 114-24, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26769916

RESUMO

The upregulated kinin B1 receptors exert a pivotal role in modulating inflammatory processes. In isolated human umbilical veins (HUVs), kinin B1 receptor is upregulated as a function of in vitro incubation time and proinflammatory stimuli. The aim of this study was to evaluate, using functional and biochemical methods, the involvement of extracellular signal-regulated kinase 5 (ERK5), p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase 1/2 (ERK1/2) on the kinin B1 receptor upregulation process in HUV. Real-time polymerase chain reaction analysis revealed for the first time that kinin B1 receptor mRNA expression closely parallels the functional sensitization to kinin B1 receptor selective agonist des-Arg(10)-kallidin (DAKD) in HUV. Moreover, the selective inhibition of ERK5, p38 MAPK, and JNK, but not ERK1/2, produced a dose-dependent rightward shift of the concentration-response curves to DAKD after 5-hour incubation and a reduction in kinin B1 receptor mRNA expression. Biochemical analyses showed that ERK5, p38 MAPK, and JNK phosphorylation is maximal during the first 2 hours postisolation, followed by a significant reduction in the last 3 hours. None of the treatments modified the responses to serotonin, an unrelated agonist, suggesting a specific effect on kinin B1 receptor upregulation. The present work provides for the first time pharmacologic evidence indicating that ERK5 plays a significant role on kinin B1 receptor upregulation. Furthermore, we confirm the relevance of p38 MAPK and JNK as well as the lack of effect of ERK1/2 in this process. This study may contribute to a better understanding of MAPK involvement in inflammatory and immunologic diseases.


Assuntos
Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Receptor B1 da Bradicinina/metabolismo , Veias Umbilicais/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Janus Quinases/metabolismo , Calidina/análogos & derivados , Calidina/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Gravidez , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Serotonina/farmacologia , Veias Umbilicais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Eur J Pharmacol ; 610(1-3): 68-74, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19289115

RESUMO

Our purposes were to perform the pharmacological characterization of PGF(2alpha) receptor (prostanoid FP-receptor) involved in human umbilical vein contraction and confirm its expression in this tissue. Umbilical cords from healthy patients after full-term deliveries were employed. The vein was dissected out of cords and used for either isolated organ bath or reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assays. The natural prostanoid FP-receptor agonist, PGF(2alpha), and its selective analogues, latanoprost and bimatoprost free acids are full agonists (produce more than 80% of the maximal contractile response to 5-HT) in human umbilical vein. The agonist potency (pEC(50)) order was PGF(2alpha) (6.01+/-0.05)>latanoprost free acid (5.65+/-0.07)=bimatoprost free acid (5.59+/-0.08). The contractile effects of PGF(2alpha) and latanoprost free acid were blocked competitively by the prostanoid FP-receptor antagonist, AL-8810. The antagonist potencies (pK(B)) of AL-8810 vs. PGF(2alpha) (5.93+/-0.05) and vs. latanoprost free acid (6.40+/-0.08) in human umbilical vein are in good agreement with its ability to antagonize prostanoid FP receptors of rat, mouse and human cells. In all samples, clear signal was detected for cDNA amplification of prostanoid FP receptor and the specific prostanoid FP-receptor antibody recognized a protein of approximately 64 kDa. In conclusion, taking into account the obtained functional and biochemical data, we propose for the first time that human umbilical vein express prostanoid FP-receptors and these receptors could be involved in the vasoconstriction action of PGF(2alpha) in this tissue.


Assuntos
Receptores de Prostaglandina/metabolismo , Veias Umbilicais/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Amidas/agonistas , Bimatoprost , Cloprostenol/agonistas , Cloprostenol/análogos & derivados , Dinoprosta/agonistas , Relação Dose-Resposta a Droga , Endotélio Vascular/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Recém-Nascido , Latanoprosta , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Prostaglandinas F Sintéticas/agonistas , Receptores de Prostaglandina/agonistas , Veias Umbilicais/citologia , Veias Umbilicais/metabolismo
7.
Eur J Pharmacol ; 602(1): 176-9, 2009 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19022239

RESUMO

The possible inhibition of kinin B(1) receptor up-regulation by arachidonoylethanolamide (anandamide) was evaluated in isolated human umbilical vein. Anandamide and its metabolically stable analogue, R-N-(2-Hydroxy-1-methylethyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (R-(+)-methanandamide), produced a selective and dose-dependent inhibition of kinin B(1) receptor-sensitized contractile responses. The inhibitory effect of anandamide on B(1) receptor-sensitized responses failed to be modified either by 5-biphenyl-4-ylmethyl-tetrazole-1-carboxylic acid dimethylamide (LY2183240), a selective anandamide uptake inhibitor, or 6-Iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indol-3-y l](4-methoxyphenyl) methanone (AM630), selective cannabinoid CB(2) receptor antagonist. However, the cannabinoid CB(1) receptor antagonist, N-(Piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophen yl)-4-methyl-1H-pyrazole-3-carboxamide (AM251), abolished anandamide effects on kinin B(1) receptor sensitization. The present results provide strong pharmacological evidence indicating that endocannabinoid anandamide inhibits kinin B(1) receptor up-regulation through cannabinoid CB(1) receptor stimulation in human umbilical vein.


Assuntos
Ácidos Araquidônicos/farmacologia , Antagonistas de Receptor B1 da Bradicinina , Moduladores de Receptores de Canabinoides/farmacologia , Endocanabinoides , Alcamidas Poli-Insaturadas/farmacologia , Receptor CB1 de Canabinoide/metabolismo , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo , Relação Dose-Resposta a Droga , Humanos , Receptor B1 da Bradicinina/metabolismo , Regulação para Cima
8.
Eur J Pharmacol ; 562(3): 227-35, 2007 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-17362923

RESUMO

Considering the potential physiological, pharmacological and therapeutic relevance of synergistic interaction of thromboxane A(2) with adrenaline at postjunctional receptor sites, we examined whether sub-threshold concentrations of thromboxane A(2) mimetic U-46619 (9,11-dideoxy-9alpha, 11alpha-methanoepoxy prostaglandin F(2alpha)) could amplify adrenaline-induced contraction in human umbilical vein. The receptor involved in U-46619-induced potentiation of adrenaline contractility was also investigated. Umbilical cords (n=125) from healthy patients after full-term vaginal or caesarean deliveries were employed. The vein was dissected out of cords and rings used for isolated organ bath experiments or reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Presence of endothelium did not modify U-46619-induced contraction in human umbilical vein. Prostanoid TP-selective receptor antagonist, SQ-29548 (7-[3-[[2-[(phenylamino)carbonyl]hydrazino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-[1S(1alpha,2alpha(Z),3alpha,4alpha)]-5-Heptenoic acid), inhibited U-46619-induced contraction (pA(2)=8.22+/-0.11). U-46619 sub-threshold concentrations (0.1-0.3 nM) potentiated adrenaline-vasoconstriction response in a concentration-dependent manner. SQ-29548 (0.1 microM) abolished this potentiation. Using RT-PCR, we found that human umbilical vein rings with or without endothelium express the prostanoid TP(alpha), but not the prostanoid TP(beta) receptor isoform. Western blot allowed the identification of proteins with an electrophoretic mobility (47- and 55-kDa) indistinguishable from human platelet prostanoid TP receptor, a rich source of prostanoid TP(alpha) receptor isoform. Collectively, present results demonstrate that prostanoid TP(alpha) is the major receptor isoform localized on smooth muscle cells which participate in both direct vasoconstriction and potentiating effects of U-46619 on adrenaline contractions in human umbilical vein. These results suggest that thromboxane A(2) may interact synergistically with adrenaline in pathophysiological situations that lead to an increase of its umbilical venous levels (e.g. preeclampsia associated with fetal distress) raising the possibility of vasoconstriction affecting fetal blood flow.


Assuntos
Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Epinefrina/farmacologia , Receptores de Tromboxanos/efeitos dos fármacos , Veias Umbilicais/efeitos dos fármacos , Vasoconstritores/farmacologia , Western Blotting , Compostos Bicíclicos Heterocíclicos com Pontes , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Endotélio Vascular/metabolismo , Ácidos Graxos Insaturados , Feminino , Humanos , Hidrazinas , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Isoformas de Proteínas/metabolismo , Receptores de Tromboxanos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Veias Umbilicais/metabolismo , Vasoconstrição/efeitos dos fármacos
9.
Naunyn Schmiedebergs Arch Pharmacol ; 375(3): 221-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17372720

RESUMO

It has been known for many years that plasma and tissues contain a variety of enzymes capable of metabolizing kinins. The aim of the present study was to evaluate, by means of functional studies in a capacitance vessel such as the human umbilical vein (HUV), the possible role played by the metallopeptidases angiotensin-converting enzyme (ACE), neutral endopeptidase (NEP), and aminopeptidase M (APM) as an inactivating pathway of the B(1) receptor endogenous agonist des-Arg(10)-kallidin (DAKD). In HUV rings with and without endothelium, concentration-response curves (CRCs) to DAKD were determined after a 300-min incubation period, and enzymatic inhibitors were added to the organ baths 30 min before construction of the CRC. Presence of endothelial layer was confirmed by histological studies. There was a significant leftward shift observed in control HUV rings devoid of endothelium compared with intact tissues. Exposure to 1 microM captopril (ACE inhibitor) potentiated DAKD-elicited vasoconstrictor responses in HUV rings with endothelium while no such effect was observed in tissues devoid of endothelium. Application of 10 microM amastatin (APM inhibitor) induced a leftward shift of DAKD-elicited contractile responses in HUV with and without endothelium. On the other hand, 10 microM phosphoramidon (NEP inhibitor) showed no potentiating effect in HUV rings either with or without endothelium. However, under concurrent inhibition of ACE, NEP and APM, there was a higher potentiation of DAKD-elicited contractile responses compared with the effect observed with combined inhibition of ACE and APM. Moreover, when we evaluated contractile responses induced by Sar(0)-D-Phe(8)-des-Arg(9)-BK (a metabolically protected B(1) receptor agonist), no potentiating effect was observed under triple enzymatic inhibition. In conclusion, in the present study for the first time, we demonstrated in a capacitance vessel, HUV, that metallopeptidases ACE, NEP and APM represent a relevant functional inactivation pathway of DAKD.


Assuntos
Inibidores Enzimáticos/farmacologia , Calidina/análogos & derivados , Veias Umbilicais/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Antígenos CD13/antagonistas & inibidores , Antígenos CD13/metabolismo , Captopril/farmacologia , Relação Dose-Resposta a Droga , Endotélio Vascular/fisiologia , Feminino , Glicopeptídeos/farmacologia , Humanos , Técnicas In Vitro , Calidina/farmacologia , Metaloproteases/antagonistas & inibidores , Metaloproteases/metabolismo , Neprilisina/antagonistas & inibidores , Neprilisina/metabolismo , Peptídeos/farmacologia , Inibidores de Proteases/farmacologia , Receptor B1 da Bradicinina/agonistas , Veias Umbilicais/enzimologia , Veias Umbilicais/fisiologia
10.
J Pharmacol Exp Ther ; 320(2): 713-20, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17085545

RESUMO

Previous reports show that bradykinin B(2) receptors mediate contractile responses induced by bradykinin (BK) in human umbilical artery (HUA). However, although it has been reported that BK-induced responses can desensitize in several inflammatory models, the effects of prolonged in vitro incubation on BK-induced vasoconstriction in HUA have not been studied. In isolated HUA rings, BK-induced responses after a 5-h in vitro incubation showed a marked desensitization compared with responses at 2 h. Inhibition of either angiotensin-converting enzyme (ACE) or neutral endopeptidase (NEP), both BK-inactivating enzymes, failed to modify responses to BK at 2 h. After 5 h, ACE inhibition produced only a slight potentiation of BK-induced responses. In contrast, BK-induced vasoconstriction at 5 h was markedly potentiated by NEP inhibition. Moreover, NEP activity, measured by hydrolysis of its synthetic substrate (Z-Ala-Ala-Leu-p-nitroanilide), showed a 2.4-fold increase in 5-h incubated versus 2-h incubated tissues, which was completely reversed by cycloheximide (CHX) treatment. Furthermore, CHX significantly potentiated BK-induced responses, suggesting that NEP-mediated kininase activity increase at 5 h depends on de novo protein synthesis. In addition, under NEP inhibition, CHX treatment failed to produce an additional potentiation of BK-induced vasoconstriction. Still, NEP up-regulation was confirmed by Western blot, showing a 2.1-fold increase in immunoreactive NEP in 5-h incubated versus 2-h incubated HUA. In summary, the present study provides strong pharmacological evidence that NEP is up-regulated and plays a key role in desensitization of BK-induced vasoconstriction after prolonged in vitro incubation in HUA. Our results provide new insights into the possible mechanisms involved in BK-induced response desensitization during sustained inflammatory conditions.


Assuntos
Bradicinina/farmacologia , Neprilisina/fisiologia , Artérias Umbilicais/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Glicopeptídeos/farmacologia , Humanos , Biossíntese de Proteínas , Receptor B1 da Bradicinina/fisiologia , Receptor B2 da Bradicinina/fisiologia , Fatores de Tempo , Artérias Umbilicais/fisiologia , Regulação para Cima
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