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1.
J Ethnopharmacol ; 333: 118476, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-38908491

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sugarcane (Saccharum officinarum L.) is reported by traditional medicine as tonic, stimulating and beneficial in increasing resistance to fatigue. Previous preclinical studies in rats using aqueous extract of sugarcane leaves (AE) revealed pharmacological effects on the central nervous and cardiovascular systems involving the participation of dopaminergic pathways. This neurotransmission system is also related to motor, emotional and cognitive activities, which could, in part, justify the ethnopharmacological information. AIM OF STUDY: The present study aimed to investigate the motor, emotional and cognitive activities of rats submitted to AE treatment using behavioral tests in order to correlate the pharmacological effects with the therapeutic benefits postulated by traditional medicine. Additionally, the chemical profile of AE was evaluated by HPLC-UV/Vis, and the presence of shikimic acid, vitexin, and ferulic acid, as possible chemical markers, was investigated through comparisons of chemical parameters with the authentic patterns, and a UV-Vis scan of known spectra. MATERIAL AND METHODS: Rats received water (1.5 mL/kg, p.o.) and AE (0.5, 10 and 500 mg/kg, p.o.) in the absence and presence of haloperidol (0.5 mg/kg, i.p.), 90 min before open field; rotarod; elevated plus maze and inhibitory avoidance tests for investigation of motor; emotional and cognitive responses. As a positive control was used apomorphine (0.25 mg/kg, s.c.). The chemical profile of AE was evaluated by HPLC-UV/Vis and the presence of shikimic acid, vitexin and ferulic acid, as possible chemical markers, was investigated through comparisons with the retention times, an increase of the integral of the peak area determined by co-injection of AE with the authentic patterns, and a UV-Vis scan of known spectra. RESULTS: In open field, it revealed that AE increased locomotion; reduced rearing but did not change freezing and grooming. Besides, AE increased motor performance in rotarod and reduced anxiety in elevated plus maze. A relation dose-response was observed in these tests where the lowest dose of AE was more effective in developing pharmacological responses. Previous administration of haloperidol inhibited the responses of AE. Inhibitory avoidance test revealed that AE did not modify fast-learning and associative memory. CONCLUSIONS: Sugarcane induced psychostimulant, anxiolytic-like effects, and improvement of motor performance in rats, with the involvement of dopaminergic pathways. The present study points to AE as a potential adaptogen but, in addition to behavioral assessments, metabolic and molecular aspects, that involve the participation of a variety of regulatory systems, will be investigated in futures studies. Phytochemical analyses showed that AE is a complex matrix and revealed shikimic acid, vitexin, and ferulic acid as potential chemical markers.


Assuntos
Ansiolíticos , Atividade Motora , Extratos Vegetais , Ratos Wistar , Saccharum , Animais , Saccharum/química , Ansiolíticos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Masculino , Ratos , Atividade Motora/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Folhas de Planta/química , Comportamento Animal/efeitos dos fármacos , Haloperidol/farmacologia , Ansiedade/tratamento farmacológico , Relação Dose-Resposta a Droga , Aprendizagem em Labirinto/efeitos dos fármacos
2.
Microbiol Spectr ; 9(3): e0017021, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34817207

RESUMO

Prenatal screening in pregnant women between 35 and 37 weeks of gestation and intrapartum antibiotic prophylaxis has successfully reduced the incidence of neonatal morbidity and mortality related to Streptococcus agalactiae. However, the contamination rates of newborns are still considerable. In traditional and folk medicines, it has been observed that garlic has been effective in treating S. agalactiae infection. The aim of this study was to isolate and identify the active compounds from garlic that have antimicrobial activity against S. agalactiae. In order to do this, SP80 (Sep-Pak 80%) obtained from crude garlic extract (CGE) was fractionated by reverse-phase ultrafast liquid chromatography with UV (RP-UFLC-UV) using a Shim-pack PREP-ODS column. All fractions obtained were tested using a microbial growth inhibition test against the S. agalactiae strain (ATCC 12386). Five clinical isolates were used to confirm the action of the fractions with antimicrobial activity, and the bacterial growth curve was determined. Identification of the antimicrobial compounds was carried out through liquid chromatography coupled with mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). The active compounds found to exhibit antimicrobial activity were Ƴ-glutamyl-S-allyl-cysteine (fraction 18), Ƴ-glutamyl-phenylalanine (fraction 20), and the two stereoisomers (E and Z) of ajoene (fraction 42). The MICs of these fractions were 5.41 mg/ml, 4.60 mg/ml, and 0.16 mg/ml, respectively, and they inhibited the growth of the clinical isolates tested. Antimicrobial compounds from garlic may be a promising source in the search for new drugs against S. agalactiae. IMPORTANCE Invasive disease due to group B streptococcal (GBS) infection results in a wide spectrum of clinical disease in neonates. Maternal colonization by GBS is the primary risk factor for disease. The strategy recommended by the Centers for Disease Control to reduce neonatal GBS infection is the culture-based screening of all pregnant women at 35 to 37 weeks of gestation and intrapartum antibiotic prophylaxis (IAP). However, indiscriminate use of antibiotics favors the selection and spread of resistant bacteria. The global scenario of antibacterial resistance has been of great concern for public health, and natural products can be a source of new substances to help us grapple with this problem.


Assuntos
Antibacterianos/farmacologia , Alho/química , Extratos Vegetais/farmacologia , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/efeitos dos fármacos , Antibacterianos/química , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus agalactiae/genética , Streptococcus agalactiae/fisiologia
3.
J Ethnopharmacol ; 271: 113885, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33539952

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Scientific evidence supports the antioxidant, anti-inflammatory and anti-lipidemic properties of Euterpe oleracea Mart. (açaí), which all converge to reduce cardiovascular risks. Macerating the pulp of açaí fruit produces a viscous aqueous extract (AE) rich in flavonoids that is commonly used in food production. In addition to nutritional aspects, cardiovascular benefits are attributed to AE by traditional medicine. AIM OF THE STUDY: Evaluation of AE impact on blood flow in vivo in rats and investigation of the mechanism underlying this response in vitro in rat endothelial cells (RECs). MATERIALS AND METHODS: For the measurement of acute blood flow, a perivascular ultrasound probe was used in Wistar rats. The in vitro assays employed REC to evaluate: concentration (1-1000 µg/mL) and time response (2-180 min) of AE in MTT cell viability assays; nitric oxide (NO) levels measurement and intracellular calcium handling using DAF-2DA and Fluo-4-AM, respectively; cellular biopterin content by HPLC; activation of Akt pathway using western blot analysis. For the chemical analyses of AE, stock solutions of the standards (+)catechin and quercetin were used for obtaining linear calibration curves. Identification and quantification of flavonoids in AE were based on comparisons with the retention times, increase in peak area determine by co-injection of AE with standards, UV-Vis scan and standard curves of known spectra. Results were expressed as mean ± standard deviation and data were analyzed using ANOVA followed by Tukey's post-test (p < 0.05). RESULTS: Although in vivo data have revealed the participation of NO in increasing of acute blood flow on abdominal aorta, in vitro analysis demonstrated that vasodilatation AE-induced is not related to its direct action on endothelial cells inducing eNOS activation. Besides, we demonstrated in isolated endothelial cells that highest concentrations of AE caused a reduction in NO levels, effect that could be partly justified by inhibition of Akt phosphorylation which, in turn, could decrease NOS activation. The involvement of cell transduction pathways involving variations in intracellular calcium and biopterins concentration were discarded. The participation of catechin and quercetin, identified in AE, was postulated to induce the responses of AE in REC. CONCLUSIONS: Despite the responses in vitro, vasodilation prevailed in vivo, probably by activating intermediate pathways, validating a potential beneficial effect of AE in reducing cardiovascular risks.


Assuntos
Circulação Sanguínea/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Euterpe/química , Extratos Vegetais/farmacologia , Animais , Biopterinas/metabolismo , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Masculino , Óxido Nítrico/metabolismo , Extratos Vegetais/uso terapêutico , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Vasodilatação/efeitos dos fármacos , Água/química
4.
Microbiol Spectr, v. 9, n. 3, e00170-21, nov. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4007

RESUMO

Prenatal screening in pregnant women between 35 and 37 weeks of gestation and intrapartum antibiotic prophylaxis has successfully reduced the incidence of neonatal morbidity and mortality related to Streptococcus agalactiae. However, the contamination rates of newborns are still considerable. In traditional and folk medicines, it has been observed that garlic has been effective in treating S. agalactiae infection. The aim of this study was to isolate and identify the active compounds from garlic that have antimicrobial activity against S. agalactiae. In order to do this, SP80 (Sep-Pak 80%) obtained from crude garlic extract (CGE) was fractionated by reverse-phase ultrafast liquid chromatography with UV (RP-UFLC-UV) using a Shim-pack PREP-ODS column. All fractions obtained were tested using a microbial growth inhibition test against the S. agalactiae strain (ATCC 12386). Five clinical isolates were used to confirm the action of the fractions with antimicrobial activity, and the bacterial growth curve was determined. Identification of the antimicrobial compounds was carried out through liquid chromatography coupled with mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). The active compounds found to exhibit antimicrobial activity were Ƴ-glutamyl-S-allyl-cysteine (fraction 18), Ƴ-glutamyl-phenylalanine (fraction 20), and the two stereoisomers (E and Z) of ajoene (fraction 42). The MICs of these fractions were 5.41 mg/ml, 4.60 mg/ml, and 0.16 mg/ml, respectively, and they inhibited the growth of the clinical isolates tested. Antimicrobial compounds from garlic may be a promising source in the search for new drugs against S. agalactiae

5.
J Ethnopharmacol ; 237: 74-80, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-30904702

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: Pimpinella anisum is used in traditional medicine because of its pharmacological properties which include cardiovascular action. However, no scientific information supports this use. AIM OF THE STUDY: This study investigated the effects of Pimpinella on arterial blood pressure (BP) and its pharmacological mechanism of action. MATERIAL AND METHODS: Pimpinella seeds were extracted with water, concentrated and freeze-dried yielding the aqueous extract (AE). A non-invasive BP assessment method was used (via the caudal artery) on Wistar, Wistar Kyoto, SHRs and rats that were submitted to high intake of dietary salt. Direct BP and heart rate were evaluated in Wistar rats in the absence or presence of atropine, L-NAME and angiotensin II. Spontaneous diuresis and the effect of AE on depolarized portal vein of Wistar rats was also examined. RESULTS: The data revealed that AE reduced BP in all groups evaluated and its effects were not due to diuretic, sympatholytic or parasympathomimetic actions. Additionally, it was shown that AE does not act as an angiotensin receptor blocker and does not induce hypotension by reducing vascular resistance induced by oxide nitric. In the depolarized portal vein, AE inhibited calcium influx, which indicates that AE acts as calcium channel blocker. CONCLUSION: This study validates the cardiovascular actions of Pimpinella and characterizes the hypotensive effects of Pimpinella that are related to the blockade of calcium channels.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Pimpinella , Extratos Vegetais/farmacologia , Animais , Bradicardia/induzido quimicamente , Cálcio/metabolismo , Hipotensão/induzido quimicamente , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ratos Wistar , Sementes
6.
J Ethnopharmacol ; 168: 45-9, 2015 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-25839118

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Pimpinella anisum L. is considered one of the first plants used for medicinal purposes. Pharmacological actions of the plant on the central nervous system have been proven but previous analyses have focused on anticonvulsant and neuroprotective actions. In traditional medicine worldwide, the use of Pimpinella is commonly recommended as a tranquilizer, although no scientific information supporting this use is available. Therefore, it was decided to investigate the central actions of the plant to observe behavioral responses, with an emphasis on the emotional component. AIM OF STUDY: To investigate the effects of the aqueous extract of Pimpinella seeds on exploratory activity and emotional behavior in rats using the open field and elevated plus maze tests. MATERIALS AND METHODS: Seeds of Pimpinella were extracted with distilled water, concentrated and freeze-dried yielding the aqueous extract(AE). Rats were divided into four groups: control(water 5 mL/kg, p.o.) and AE 0.5, 1.0 and 2.0 g/kg, p.o. Individual observations were performed in an open field and the parameters locomotor activity, rearing, grooming and defecation were recorded. In elevated plus maze test, rats were divided into four groups: control(water 5 mL/kg, p.o.) and AE 0.5, 1.0 and 2.0 g/kg, p.o. The parameters arm entries, total time spent in open and closed arms; and total number of arrivals at the end of an open or closed arm were recorded for each rat. RESULTS: Among the parameters assessed with the open field test, only rearing was reduced in the AE 0.5 g/kg group. When AE 1.0 g/kg was administered, only the initiation of exploratory activity was delayed, without impairing the animals' general activity. The highest dose of AE (2.0 g/kg) induced a reduction in the animals' habituation during the open field test within the same session, as evidenced by the maintenance of high levels of peripheral locomotion and rearing throughout the test. On the elevated plus maze test, no alterations were observed in the responses of the animals relative to controls for all doses tested. CONCLUSION: These results failed to support anxiety-related central action of the aqueous extract of Pimpinella seeds, invalidating popular beliefs regarding a tranquilizing effect. However, a habituation-related central action of the extract was demonstrated, suggesting action of bioactive compounds on central learning-related areas. The characterization of effects that may interfere with cognitive processes reinforces caution regarding indiscriminate consumption of the plant, especially in individuals with deficits, such as Alzheimer's Disease patients.


Assuntos
Pimpinella , Extratos Vegetais/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Aprendizagem em Labirinto , Ratos Wistar , Sementes
7.
Neurosci Lett ; 531(2): 91-5, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23041487

RESUMO

The interaction between dopaminergic and cholinergic pathways in the induction of behavioral responses has been previously established. In the brain, M2 receptors are found predominantly in presynaptic cholinergic neurons as autoreceptors, and in dopaminergic neurons as heteroceptors, suggesting a control role of acetylcholine and dopamine release, respectively. Our aim was to investigate the role of M2 receptors on the yawning and genital grooming of rats induced by apomorphine, a dopaminergic receptor agonist, focusing on the interaction between cholinergic and dopaminergic pathways. Initially, the effect of atropine, a non-selective muscarinic antagonist, on yawning and genital grooming induced by apomorphine (100 µg/kg s.c.) was analyzed. Atropine doses of 0.5, 1 and 2 mg/kg i.p. were administered to Wistar rats 30 min before induction of the behavioral responses by apomorphine. Number of yawns and time spent genital grooming were quantified over a 60 min period. Apomorphine-induced yawning was increased by low dose (0.5 mg/kg i.p.) but not by high doses (1 and 2 mg/kg, i.p.) of atropine. Genital grooming was antagonized by 2 mg/kg i.p. of atropine and showed no changes at the other doses tested. Tripitramine, a selective M2 cholinergic antagonist, was used as a tool for distinguishing between M2 and all other muscarinic receptor subtypes in yawning and genital grooming. Tripitramine doses of 0.01, 0.02 and 0.04 µmol/kg i.p. were administered to Wistar rats 30 min before apomorphine (100 µg/kg s.c.). Number of yawns and time spent genital grooming were also quantified over a 60 min period. Tripitramine 0.01 µmol/kg increased all parameters. Higher doses, which possibly block all subtypes of muscarinic receptor, did not modify the response of apomorphine, suggesting a non-selective effect of tripitramine at these doses. Given that low doses of tripitramine increased the behavioral responses induced by apomorphine and that the main distribution of the M2 receptor is presynaptic, we raised the hypothesis that tripitramine may alter cholinergic and/or dopaminergic transmission in brain areas responsible for induction of yawning and genital grooming in rats, possibly by control of acetylcholine and/or dopamine release. In addition, the present study showed the involvement of M2 cholinergic receptors in the complex mechanisms of functional interactions between dopaminergic and cholinergic systems involved in the control of yawning and genital grooming.


Assuntos
Asseio Animal/fisiologia , Receptor Muscarínico M2/metabolismo , Bocejo/fisiologia , Animais , Apomorfina/farmacologia , Agonistas de Dopamina/farmacologia , Ratos , Ratos Wistar
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