RESUMO
INTRODUCTION: Citral is a low-toxicity monoterpene that has a vasodilator effect on various smooth muscles, and The present study aimed to evaluate its vasorelaxant effect on umbilical vessels of normotensive parturients (NTP) and with preeclampsia parturients (PEP). METHOD: Segments of human umbilical artery (HUA) and vein (HUV) of NTP or PEP were mounted in a bath to record the force of contraction, under tension of 3.0 gf and contracted with the contracting agents: K+ (60 mM), 5 -HT (10 µM) and Ba2+ (1-30 mM). Next, the effect of citral (1-3000 µM) on these contractions and on basal tone was evaluated. RESULTS: In HUA and HUV, citral (1-1000 µM), in NTP condition, inhibited contractions evoked by K+ (IC50 of 413.5 and 271.3, respectively) and by 5-HT (IC50 of 164.8 and 574.3). In the PEP condition, in HUA and HUV, citral also inhibited the contractions evoked by K+ (IC50 of 363.3 and 218.3, respectively) and 5-HT (IC50 of 432.1 and 520.4). At a concentration of 1000 µM, citral completely or almost completely (>90 %) inhibited all contractions. At a concentration of 100-1000 µM, citral, in general, was already able to reduce the contraction induced by 1-3 mM Ba2+ in both AUH and VUH, under NTP and PEP conditions. DISCUSSION: Citral has been shown to be an effective HUA and HUV vasodilator in NTP and PEP. As its toxicity is low, it suggests that this substance can be considered a potential therapeutic agent.
Assuntos
Monoterpenos Acíclicos , Monoterpenos , Pré-Eclâmpsia , Artérias Umbilicais , Vasodilatadores , Humanos , Feminino , Gravidez , Pré-Eclâmpsia/fisiopatologia , Monoterpenos Acíclicos/farmacologia , Monoterpenos/farmacologia , Artérias Umbilicais/efeitos dos fármacos , Adulto , Vasodilatadores/farmacologia , Veias Umbilicais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacosRESUMO
BACKGROUND: Perillyl alcohol (POH) is a monoterpenoid found in plant essential oils and has been shown to relax murine vessels, but its effect on human vessels remains poorly studied. OBJECTIVE: The study aimed to characterize the effect of POH on human umbilical arteries (HUA). METHODS: Rings of HUA were obtained from uncomplicated patients and suspended in an organ bath for isometric recording. The vasorelaxant effect of POH in HUA was evaluated on basal tone and electromechanical or pharmacomechanical contractions, and possible mechanisms of action were also investigated. RESULTS: POH (1-1000 µM) altered the basal tone of HUA and completely relaxed HUA rings precontracted with KCl (60 mM) or 5-HT (10 µM), obtaining greater potency in the pharmacomechanical pathway (EC50 110.1 µM), suggesting a complex interference in the mobilization of extra- and intracellular Ca2+. POH (1000 µM) inhibited contractions induced by BaCl2 (0.1-30 mM) in a similar way to nifedipine (10 µM), indicating a possible blockade of L-type VOCC. In the presence of potassium channel blockers, tetraethylammonium (1 mM), 4-aminopyridine (1 mM), or glibenclamide (10 µM), an increase in the EC50 value of the POH was observed, suggesting a modulation of the activity of BKCa, KV, and KATP channels. CONCLUSION: The data from this study suggest that POH modulates Ca2+ and K+ ion channels to induce a relaxant response in HUA.
RESUMO
BACKGROUND: Naturally occurring bioactive compounds have a plethora of biological effects. OBJECTIVE: In this study, we examined a pharmacological screening of natural products on the human umbilical artery (HUA). METHODS: HUA preparations were used to follow contractions by KCl (60 mM) and tested at different concentrations (1-5000 µg/mL and µM) of the Lippia alba (EOLa) and Lippia origanoides (EOLo) essential oils, terpenes (citral, limonene perilic alcohol) and phenylpropanoids (eugenol, methyl eugenol). Discussion/Results: The reduction corresponded to approximately 100%, except for limonene (80±1.2 %). When evaluating the concentration of the natural product that promotes 50 % relaxation of the HUA contracted by KCL, EC50 values were: 424.3 µg/mL (EOLa); 468.7±6.7 µg/mL (EOLo); 264.2 ± 8.2 µM (citral); 677.8±5.4 µM (limonene); 186.3±6.4 µM (peryl alcohol); 986.4±7.9 µM (eugenol); and 279.1±4.4 µM (methyl-eugenol). Perillyl alcohol had a lower EC50 (consequently it has a higher pharmacological potency). CONCLUSION: The plant extracts have a promising vasorelaxing effect in HUAs, paving the way for future investigations: as applications in diseases related to these vessels, such as preeclampsia.
RESUMO
Lippia alba is popularly known as lemon balm, with its essential oil (EO) cited for displaying antimicrobial, sedative, and vasorelaxant effects. Yet, its action on isolated human vessels has not been described in the literature. Thus, we evaluated the vasorelaxant effect of essential oil of L. alba (EOLa) on human umbilical arteries (HUA) isolated in organ baths. HUA rings were isolated, subjected to contractions induced by potassium chloride (KCl), serotonin (5-HT), or histamine (HIST) to record the isometric tension, and then treated with EOLa (30-1000 µg/mL). The EOLa showed a more prominent inhibitory effect on the pharmacomechanical coupling contraction via HIST with an EC50 value of 277.1 ± 8.5 µg/mL and maximum relaxant effect at 600 µg/mL. The addition of tetraethylammonium (TEA) or 4-aminopyridine (4-AP) in HUA preparations did not inhibit EOLa total relaxant effect at 1000 µg/mL. In the presence of gliblenclamide (GLI), the oil relaxed the HUA rings by 90.8% at maximum concentration. The EOLa was also investigated for its effects on voltage-operated calcium channels (VOCCs), where the HUA preincubation with this oil at 1000 µg/mL inhibited BaCl2 (0.1-30 mM)-induced contractions. This study demonstrates for the first time that EOla has a vasorelaxant effect on HUA and its particular blockade of VOCCs.
RESUMO
PURPOSE: Alternative methods for the use of animals in research have gained increasing importance, due to assessments evaluating the real need for their use and the development of legislation that regulates the subject. The principle of the 3R's (replacement, reduction and refinement) has been an important reference, such that in vitro, ex vivo and cord replacement methods have achieved a prominent place in research. METHODS: Therefore, due to successful results from studies developed with these methods, the present study aimed to evaluate the myorelaxant effect of the Dysphania ambrosioides essential oil (EODa) using a Sus scrofa domesticus coronary artery model, and the toxicity of both the Dysphania ambrosioides essential oil and its major constituent, α-terpinene, against Drosophila melanogaster in toxicity and negative geotaxis assays. RESULTS: The EODa relaxed the smooth muscle of swine coronary arteries precontracted with K+ and 5-HT in assays using Sus scrofa domesticus coronary arteries. The toxicity results presented LC50 values of 1.546 mg/mL and 2.282 mg/mL for the EODa and α-terpinene, respectively, thus showing the EODa and α-terpinene presented toxicity to these dipterans, with the EODa being more toxic. CONCLUSIONS: Moreover, the results reveal the possibility of using the EODa in vascular disease studies since it promoted the relaxation of the Sus scrofa domesticus coronary smooth muscle.
Assuntos
Chenopodiaceae/química , Vasos Coronários/fisiologia , Drosophila melanogaster/fisiologia , Relaxamento Muscular/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Voláteis/toxicidade , Testes de Toxicidade , Animais , Vasos Coronários/efeitos dos fármacos , Monoterpenos Cicloexânicos/farmacologia , Modelos Animais de Doenças , Drosophila melanogaster/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Compostos Fitoquímicos/análise , Serotonina/farmacologia , SuínosRESUMO
Caffeic acid is a phenolic compound widely found in commonly consumed foods such as pears, apples and coffee, and is pharmacologically known for its antioxidant, anti-inflammatory and anti-asthmatic properties. However, its relaxant activity in the aorta, uterus and ileum smooth muscle has not been investigated. This study aimed to comparatively evaluate the effect of caffeic acid on smooth muscle from different organs (aorta, uterus and ileum), and the contractions of this different organ were induced by different agonists. The organ bath technique was used, where the organs were placed in different cuvettes with 10 mL of Tyrode solution for 1 h to stabilize, then, myometrial, intestinal strip and aortic ring contractions were evoked using different contractile agonists (KCl 60 mM, PHE 0.1 µM, OT 10-2 IU/mL, CCh 10-6 M and BaCl2 0.1-30 mM); increasing concentrations of caffeic acid (0.03-7 mM) were administered in the experimental preparations. In the presence of KCl (60 mM), caffeic acid caused relaxations with the following EC50 values: 2.7 ± 0.26 mM/mL (aorta), 5.7 ± 0.71 mM/mL (uterus) and 2.1 ± 0.39 mM/mL (ileum). When in the presence of different agonists, PHE (0.1 µM) for the aorta, OT (10-2 IU/mL) for the uterus and CCh (10-6 M) for the ileum, caffeic acid caused relaxations with EC50 values of: 2.7 ± 0.31 mM/mL; 2.2 ± 0.34 mM/mL and 2.0 ± 0.28 mM/mL, respectively. The inhibitory effect of caffeic acid on serotonergic (aorta and uterus) and muscarinic receptors (uterus and ileum), as well as its possible involvement with L-type Ca2+ channels, was also observed. This study reports the pharmacological characterization of caffeic acid on smooth muscle from different organs, for which caffeic acid was more potent in the ileum. A diverse understanding of its performance as a possible therapeutic product is attributed to its relaxant effect.
Assuntos
Aorta/fisiologia , Ácidos Cafeicos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Íleo/fisiologia , Músculo Liso/fisiologia , Fenóis/farmacologia , Útero/fisiologia , Animais , Aorta/efeitos dos fármacos , Ácidos Cafeicos/química , Canais de Cálcio Tipo L/metabolismo , Carbacol/farmacologia , Feminino , Íleo/efeitos dos fármacos , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Ocitocina/farmacologia , Fenóis/química , Fenilefrina/farmacologia , Cloreto de Potássio , Ratos Wistar , Útero/efeitos dos fármacosRESUMO
Carveol is a monoterpene present in the structure of many plant products. It has a variety of biological activities: antioxidant, anticancer and vasorelaxation. However, studies investigating the effect of monoterpenoids on human vessels have not yet been described. Thus, the present study aimed to characterize the effect of (-)-carveol on human umbilical arteries (HUAs). HUA ring preparations were isolated and subjected to isometric tension recordings of umbilical artery smooth muscle contractions. (-)-Carveol exhibited a significant vasorelaxant effect on KCl and 5-HT-induced contractions, obtaining EC50 values of 344.25 ± 8.4 and 175.82 ± 4.05 µM, respectively. The participation of calcium channels in the relaxation produced by (-)-carveol was analyzed using vessels pre-incubated with (-)-carveol (2000 µM) in a calcium-free medium, where the induction of contractions was abolished. The vasorelaxant effect of (-)-carveol on HUAs was reduced by tetraethylammonium (TEA), which increased the (-)-carveol EC50 to 484.87 ± 6.55 µM. The present study revealed that (-)-carveol possesses a vasorelaxant activity in HUAs, which was dependent on the opening of calcium and potassium channels. These results pave the way for further studies involving the use of monoterpenoids for the vasodilatation of HUAs. These molecules have the potential to treat diseases such as pre-eclampsia, which is characterized by resistance in umbilical arteries.
Assuntos
Canais de Cálcio/fisiologia , Monoterpenos Cicloexânicos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Canais de Potássio/fisiologia , Artérias Umbilicais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Canais de Cálcio/efeitos dos fármacos , Endotélio Vascular/metabolismo , Feminino , Humanos , Canais de Potássio/efeitos dos fármacos , Artérias Umbilicais/metabolismoRESUMO
A grande maioria dos estudos que envolvem a investigação da ação de substâncias de origem natural terapeuticamente promissora associadas às fisiopatologias que acometem a musculatura lisa, utiliza-se de modelos de músculo liso isolados de animais de laboratórios, onde dependem unicamente desse método para o desenvolvimento de pesquisas. Na região do Cariri encontram-se inúmeras instituições de ensino que ainda dependem de animais para pesquisa, em especial a Universidade Regional do Cariri-URCA conta com programas de pós-graduação onde algumas linhas de pesquisa dependem unicamente desse método. Os aspectos éticos da utilização de animais em experimentos estimulam a adoção de métodos alternativos sempre que possível. O presente trabalho é um relato de experiência que pretende demonstrar como se encontra a situação da pesquisa científica frente aos métodos alternativos que estão sendo implementados no Laboratório de Fisiofarmacologia das Células Excitáveis da URCA, para substituição ao uso de animais laboratoriais, obedecendo assim, a regra dos 3Rs. São utilizados cordões umbilicais, obtidos de partos normais no bloco de obstetrícia do Hospital e Maternidade São Francisco de Assis, e órgãos suínos providos de animais abatidos para consumo de carne, obtidos do abatedouro Frigorífico Industrial do Cariri. Os experimentos estão sendo desenvolvidos com a técnica de banho de órgãos, verificando o efeito miorrelaxante de produtos naturais. Pesquisas como monografias, dissertações e teses estão sendo desenvolvidas. Os vasos umbilicais e bronquíolos de suínos estão substituindo respectivamente o uso de artéria aorta e traqueia de ratos. Com isso, vimos que é possível reduzir e substituir o número de animais eutanasiados com finalidade de pesquisa científica.
The great majority of the studies involving the investigation of the action of therapeutically promising natural substances associated to the pathophysiologies that affect the smooth muscle, use of smooth muscle models isolated from laboratory animals, where they depend solely on this method for the development of researches. In the Cariri region there are numerous educational institutions that still depend on animals for research, in particular the Regional University of Cariri-URCA has postgraduate programs where some lines of research depend solely on this method. The ethical aspects of using animals in experiments encourage the adoption of alternative methods whenever possible. The present work is an experience report that intends to demonstrate how the situation of the scientific research is faced with the alternative methods being implemented in the Laboratory of Physiopharmacology of Excitable Cells of URCA, to replace the use of laboratory animals, obeying the 3Rs rule. Umbilical cords, obtained from normal deliveries in the obstetric block of the São Francisco de Assis Hospital and Maternity Unit, and swine organs provided with animals slaughtered for meat consumption, obtained from the slaughterhouse Frigorífico Industrial do Cariri, are used. The experiments are being developed with the organ bath technique, verifying the myorelaxant effect of natural products. Researches such as monographs, dissertations and theses are being developed. The umbilical vessels and bronchioles of pigs are respectively replacing the use of the aorta and trachea of rats. With this, we have seen that it is possible to reduce and replace the number of euthanized animals for scientific research purposes.
Assuntos
Animais , Alternativas ao Uso de Animais/métodos , Animais de Laboratório , Músculo Liso , Experimentação AnimalRESUMO
A grande maioria dos estudos que envolvem a investigação da ação de substâncias de origem natural terapeuticamente promissora associadas às fisiopatologias que acometem a musculatura lisa, utiliza-se de modelos de músculo liso isolados de animais de laboratórios, onde dependem unicamente desse método para o desenvolvimento de pesquisas. Na região do Cariri encontram-se inúmeras instituições de ensino que ainda dependem de animais para pesquisa, em especial a Universidade Regional do Cariri-URCA conta com programas de pós-graduação onde algumas linhas de pesquisa dependem unicamente desse método. Os aspectos éticos da utilização de animais em experimentos estimulam a adoção de métodos alternativos sempre que possível. O presente trabalho é um relato de experiência que pretende demonstrar como se encontra a situação da pesquisa científica frente aos métodos alternativos que estão sendo implementados no Laboratório de Fisiofarmacologia das Células Excitáveis da URCA, para substituição ao uso de animais laboratoriais, obedecendo assim, a regra dos 3Rs. São utilizados cordões umbilicais, obtidos de partos normais no bloco de obstetrícia do Hospital e Maternidade São Francisco de Assis, e órgãos suínos providos de animais abatidos para consumo de carne, obtidos do abatedouro Frigorífico Industrial do Cariri. Os experimentos estão sendo desenvolvidos com a técnica de banho de órgãos, verificando o efeito miorrelaxante de produtos naturais. Pesquisas como monografias, dissertações e teses estão sendo desenvolvidas. Os vasos umbilicais e bronquíolos de suínos estão substituindo respectivamente o uso de artéria aorta e traqueia de ratos. Com isso, vimos que é possível reduzir e substituir o número de animais eutanasiados com finalidade de pesquisa científica.(AU)
The great majority of the studies involving the investigation of the action of therapeutically promising natural substances associated to the pathophysiologies that affect the smooth muscle, use of smooth muscle models isolated from laboratory animals, where they depend solely on this method for the development of researches. In the Cariri region there are numerous educational institutions that still depend on animals for research, in particular the Regional University of Cariri-URCA has postgraduate programs where some lines of research depend solely on this method. The ethical aspects of using animals in experiments encourage the adoption of alternative methods whenever possible. The present work is an experience report that intends to demonstrate how the situation of the scientific research is faced with the alternative methods being implemented in the Laboratory of Physiopharmacology of Excitable Cells of URCA, to replace the use of laboratory animals, obeying the 3Rs rule. Umbilical cords, obtained from normal deliveries in the obstetric block of the São Francisco de Assis Hospital and Maternity Unit, and swine organs provided with animals slaughtered for meat consumption, obtained from the slaughterhouse Frigorífico Industrial do Cariri, are used. The experiments are being developed with the organ bath technique, verifying the myorelaxant effect of natural products. Researches such as monographs, dissertations and theses are being developed. The umbilical vessels and bronchioles of pigs are respectively replacing the use of the aorta and trachea of rats. With this, we have seen that it is possible to reduce and replace the number of euthanized animals for scientific research purposes.(AU)