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1.
Sci Rep ; 12(1): 3512, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241736

RESUMO

The shortage of intensive care unit (ICU) resources, including equipment and supplies for renal replacement therapy (RRT), is a critical problem in several countries. This study aimed to assess hospital mortality and associated factors in patients treated in public hospitals of the Federal District, Brazil, who requested admission to ICU with renal replacement therapy support (ICU-RRT) in court. Retrospective cohort study that included 883 adult patients treated in public hospitals of the Federal District who requested ICU-RRT admission in court from January 2017 to December 2018. ICU-RRT was denied to 407 patients, which increased mortality (OR 3.33, 95% CI 2.39-4.56, p ≪ 0.01), especially in patients with priority level I/II (OR 1.02, 95% CI 1.01-1.04, p ≪ 0.01). Of the requests made in court, 450 were filed by patients with priority levels III/IV, and 44.7% of these were admitted to ICU-RRT. In admitted patients, priority level III priority level I/II was associated with a low mortality (OR 0.47, 95% CI 0.32-0.69, p < 0.01), and not. The admission of patients classified as priority levels III/IV to ICU-RRT considerably jeopardized the admission of patients with priority levels I/II to these settings. The results found open new avenues for organizing public policies and improving ICU-RRT triage.


Assuntos
Injúria Renal Aguda , Injúria Renal Aguda/etiologia , Adulto , Brasil , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Terapia de Substituição Renal/efeitos adversos , Estudos Retrospectivos
2.
Biomed Res Int ; 2019: 1871239, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31119154

RESUMO

Pathogenic species of mycobacteria are known to use the host cholesterol during lung infection as an alternative source of carbon and energy. Mycobacteria culture in minimal medium (MM) has been used as an in vitro experimental model to study the consumption of exogenous cholesterol. Once in MM, different species of mycobacteria start to consume the cholesterol and initiate transcriptional and metabolic adaptations, upregulating the enzymes of the methylcitrate cycle (MCC) and accumulating a variety of primary metabolites that are known to be important substrates for cell wall biosynthesis. We hypothesized that stressful pressure of cultures in MM is able to induce critical adaptation for the bacteria which win the infection. To identify important modifications in the biosynthesis of the cell wall, we cultured the fast-growing and nonpathogenic Mycobacterium smegmatis in MM supplemented with or without glycerol and/or cholesterol. Different from the culture in complete medium Middlebrook 7H9 broth, the bacteria when cultured in MM decreased growth and changed in the accumulation of cell wall molecules. However, the supplementation of MM with glycerol and/or cholesterol recovered the accumulation of phosphatidylinositol mannosides (PIMs) and other phospholipids but maintained growth deceleration. The biosynthesis of lipomannan (LM) and of lipoarabinomannan (LAM) was significantly modulated after culture in MM, independently of glycerol and/or cholesterol supplementation, where LM size was decreased (LM13-25KDa) and LAM increased (LAM37-100KDa), when compared these molecules after bacteria culture in complete medium (LM17-25KDa and LAM37-50KDa). These changes modified the cell surface hydrophobicity and susceptibility against H2O2. The infection of J774 macrophages with M. smegmatis, after culture in MM, induced the formation of granuloma-like structures, while supplementation with cholesterol induced the highest rate of formation of these structures. Taken together, our results identify critical changes in mycobacterial cell wall molecules after culture in MM that induces cholesterol accumulation, helping the mycobacteria to increase their capacity to form granuloma-like structures.


Assuntos
Parede Celular/metabolismo , Microambiente Celular/efeitos dos fármacos , Colesterol/farmacologia , Mycobacterium smegmatis/metabolismo , Membrana Celular/metabolismo , Parede Celular/efeitos dos fármacos , Meios de Cultura/química , Meios de Cultura/farmacologia , Granuloma/metabolismo , Granuloma/patologia , Peróxido de Hidrogênio/farmacologia , Lipopolissacarídeos/biossíntese , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Mycobacterium smegmatis/efeitos dos fármacos , Mycobacterium smegmatis/patogenicidade
3.
J Ethnopharmacol ; 118(3): 455-9, 2008 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-18579323

RESUMO

Tabebuia avellanedae is commonly used for the treatment of peptic ulcers. We carried out this study with the ethanolic extract of bark from Tabebuia avellanedae (EET) (30-1000 mg/kg) to determine its gastroprotective activity and to clarify the pathways involved in this effect. Acute gastric ulceration in rats was produced by oral administration of ethanol and ibuprofen. After ethanol administration, the gastric wall mucus was examined. Chronic gastric ulceration was produced by injection of acetic acid in rat gastric subserosa. Anti-secretory studies were undertaken using Shay rat pylorus ligature technique and measurement of enzymatic activity of H+, K+-ATPase in vitro. Administration of EET p.o. or i.p. significantly inhibited gastric mucosa damage induced by ethanol and ibuprofen. The anti-ulcer effect was further confirmed by enhanced gastric mucus production. In pylorus ligature rats, EET significantly reduced the basal gastric acid secretion and total acidity; moreover, it inhibited the increase in total acidity induced by histamine. In addition, EET reduced the activity of H+, K+, ATPase. The results obtained in the present pharmacological assay indicate that this plant has a protective action against gastric lesions, involving the maintenance of protective factors, such as mucus and prostaglandin, besides the reduction of gastric total acidity.


Assuntos
Antiulcerosos/farmacologia , Extratos Vegetais/farmacologia , Tabebuia , Animais , Feminino , Ácido Gástrico/metabolismo , Mucosa Gástrica/efeitos dos fármacos , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Ibuprofeno/toxicidade , Camundongos , Fitoterapia , Casca de Planta/química , Ratos , Ratos Wistar , Úlcera Gástrica/tratamento farmacológico
4.
Front Aging Neurosci ; 10: 334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30450044

RESUMO

Despite advances in the treatment of Alzheimer's disease (AD), there is currently no prospect of a cure, and evidence shows that multifactorial interventions can benefit patients. A promising therapeutic alternative is the use of transcranial direct current stimulation (tDCS) simultaneously with cognitive intervention. The combination of these non-pharmacological techniques is apparently a safe and accessible approach. This study protocol aims to compare the efficacy of tDCS and cognitive intervention in a double-blind, randomized and factorial clinical trial. One hundred participants diagnosed with mild-stage AD will be randomized to receive both tDCS and cognitive intervention, tDCS, cognitive intervention, or placebo. The treatment will last 8 weeks, with a 12-month follow-up. The primary outcome will be the improvement of global cognitive functions, evaluated by the AD Assessment Scale, cognitive subscale (ADAS-Cog). The secondary outcomes will include measures of functional, affective, and behavioral components, as well as a neurophysiological marker (Brain-derived neurotrophic factor, BDNF). This study will enable us to assess, both in the short and long term, whether tDCS is more effective than the placebo and to examine the effects of combined therapy (tDCS and cognitive intervention) and isolated treatments (tDCS vs. cognitive intervention) on patients with AD. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02772185-May 5, 2016.

5.
Scand J Work Environ Health ; 41(4): 384-396, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25940455

RESUMO

OBJECTIVES: We assessed whether maternal employment during pregnancy - overall and in selected occupational sectors - is associated with birth weight, small for gestational age (SGA), term low birth weight (LBW), length of gestation, and preterm delivery in a population-based birth cohort design. METHODS: We used data from >200 000 mother-child pairs enrolled in 13 European birth cohorts and compared employed versus non-employed women. Among employees, we defined groups of occupations representing the main sectors of employment for women where potential reproductive hazards are considered to be present. The comparison group comprised all other employed women not included in the occupational sector being assessed. We performed meta-analyses of cohort-specific estimates and explored heterogeneity. RESULTS: Employees had a lower risk of preterm delivery than non-employees [adjusted odds ratio (OR adj) 0.86, 95% confidence interval (95% CI) 0.81-0.91]. Working in most of the occupational sectors studied was not associated with adverse birth outcomes. Being employed as a nurse was associated with lower risk SGA infants (OR adj0.91, 95% CI 0.84-0.99) whereas food industry workers had an increased risk of preterm delivery (OR adj1.50, 95% CI 1.12-2.02). There was little evidence for heterogeneity between cohorts. CONCLUSIONS: This study suggests that, overall, employment during pregnancy is associated with a reduction in the risk of preterm birth and that work in certain occupations may affect pregnancy outcomes. This exploratory study provides an important platform on which to base further prospective studies focused on the potential consequences of maternal occupational exposures during pregnancy on child development.


Assuntos
Peso ao Nascer , Emprego/classificação , Exposição Materna/efeitos adversos , Ocupações/classificação , Resultado da Gravidez/epidemiologia , Estudos de Coortes , Emprego/estatística & dados numéricos , Europa (Continente)/epidemiologia , Feminino , Idade Gestacional , Comportamentos Relacionados com a Saúde , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Exposição Materna/estatística & dados numéricos , Metanálise como Assunto , Ocupações/estatística & dados numéricos , Gravidez , Nascimento Prematuro , Análise de Regressão , Fatores de Risco , Inquéritos e Questionários
6.
J Biochem Biophys Methods ; 50(2-3): 129-40, 2002 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-11741702

RESUMO

Phosphofructokinase-1 plays a key role in the regulation of carbohydrate metabolism. Its activity can be used as an indicator of the glycolytic flux in a tissue sample. The method most commonly employed to determine phosphofructokinase-1 activity is based on oxidation of NADH by the use of aldolase, triosephosphate isomerase, and alpha-glycerophosphate dehydrogenase. This method suffers from several disadvantages, including interactions of the auxiliary enzymes with phosphofructokinase-1. Other methods that have been used also require auxiliary enzymes or are less sensitive than a coupled assay. Here, we propose a direct method to determine phosphofructokinase-1 activity, without the use of auxiliary enzymes. This method employs fructose-6-phosphate and ATP labeled with 32P in the gamma position ([gamma-32P]ATP), and leads to the formation of ADP and fructose-1,6-bisphosphate labeled with 32P ([1-32P]fructose-1,6-bisphosphate). Activated charcoal is used to adsorb unreacted [gamma-32P]ATP, and the radioactive product in the supernatant, [1-32P]fructose-1,6-bisphosphate, is analyzed on a liquid scintillation counter. The proposed method is precise and relatively inexpensive, and can be applied to determine phosphofructokinase-1 activity in cellular extracts as well as in the purified enzyme.


Assuntos
Fosfofrutoquinase-1/análise , Trifosfato de Adenosina , Animais , Chlorocebus aethiops , Eritrócitos/enzimologia , Frutosefosfatos , Humanos , Cinética , Músculo Esquelético/enzimologia , Fosfofrutoquinase-1/sangue , Fosfofrutoquinase-1/isolamento & purificação , Fosfofrutoquinase-1 Muscular/análise , Fosfofrutoquinase-1 Muscular/isolamento & purificação , Radioisótopos de Fósforo , Coelhos , Radiometria/métodos , Contagem de Cintilação , Espectrofotometria/métodos , Especificidade por Substrato , Células Vero
7.
Food Chem Toxicol ; 51: 179-87, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23036453

RESUMO

We evaluate the curative efficacy of the ethanolic extract (EET) of roots from Arctium lappa (bardana) in healing of chronic gastric ulcers induced by 80% acetic acid in rats and additionally studies the possible mechanisms underlying this action. Oral administration of EET (1, 3, 10 and 30mg/kg) reduced the gastric lesion area in 29.2%, 41.4%, 59.3% and 38.5%, respectively, and at 10mg/kg promoted significant regeneration of the gastric mucosa, which was confirmed by proliferating cell nuclear antigen immunohistochemistry. EET (10mg/kg) treatment did not increase the gastric mucus content but restored the superoxide dismutase activity, prevented the reduction of glutathione levels, reduced lipid hydroperoxides levels, inhibited the myeloperoxidase activity and reduced the microvascular permeability. In addition, EET reduced the free radical generation and increased scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals in vitro. Furthermore, intraduodenal EET (10 and 30mg/kg) decreased volume and acidity of gastric secretion. Total phenolic compounds were high in EET (Folin-Ciocalteau assay) and the analysis by liquid chromatography-mass spectrometry revealed that the main compounds present in EET were a serie of hydroxycinnamoylquinic acid isomers. In conclusion, these data reveal that EET promotes regeneration of damaged gastric mucosa, probably through its antisecretory and antioxidative mechanisms.


Assuntos
Antiulcerosos/farmacologia , Arctium/química , Extratos Vegetais/farmacologia , Úlcera Gástrica/tratamento farmacológico , Ácido Acético/toxicidade , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Etanol/química , Feminino , Radicais Livres/metabolismo , Ácido Gástrico/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Glutationa/metabolismo , Peroxidase/metabolismo , Fenóis/análise , Extratos Vegetais/química , Raízes de Plantas/química , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia , Superóxido Dismutase/metabolismo
8.
Nat Prod Commun ; 6(9): 1253-4, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21941891

RESUMO

H+, K(+)-ATPase enzyme is a therapeutic target for the treatment of gastric disturbances. Several medicinal plants and isolated compounds inhibit the acid gastric secretion through interaction with the proton pump. In order to add new properties to some natural constituents, five compounds, a benzylated derivative of vincoside, a diterpene (abietic acid) and three alkaloids (cephaeline, vinblastine and vindoline), were tested for their activities on gastric H+, K(+)-ATPase isolated from rabbit stomach. All the compounds inhibited H+, K(+)-ATPase activity with varied potency. The IC50 value for benzylvincoside was 121 (50-293) microM, and for abietic acid 177 (148-211) microM. The alkaloids cephaeline, vinblastine and vindoline inhibited the H+, K(+)-ATPase activity with IC50 values of 194, 761 and 846 microM, respectively. The results suggest that benzylvincoside, abietic acid and cephaeline can be important sources for the development of anti-secretor agents.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Plantas Medicinais/química , Inibidores da Bomba de Prótons , Animais , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Masculino , Coelhos
9.
J Ethnopharmacol ; 130(1): 85-92, 2010 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-20420892

RESUMO

UNLABELLED: Achillea millefolium L. is a member of the Asteraceae family that is commonly referred to as "yarrow" and has been used in folk medicine against several disturbances including skin inflammations, spasmodic and gastrointestinal disorders, as well as hepato-biliary complaints. AIM OF THE STUDY: In the present study, we evaluated the efficacy of a hydroalcoholic extract from the Achillea millefolium (HE) for gastroprotective properties and additional mechanism(s) involved in this activity. MATERIAL AND METHODS: Rats were treated with HE and subsequently exposed to both acute gastric lesions induced by ethanol P.A. and chronic gastric ulcers induced by 80% acetic acid. Following treatment, glutathione (GSH) levels and superoxide dismutase (SOD) activity were measured. The activity of myeloperoxidase (MPO) and histological and immunohistochemical analysis were performed in animals with acetic acid-induced gastric ulcers. RESULTS: Oral administration of HE (30, 100 and 300mg/kg) inhibited ethanol-induced gastric lesions by 35, 56 and 81%, respectively. Oral treatment with HE (1 and 10mg/kg) reduced the chronic gastric ulcers induced by acetic acid by 43 and 65%, respectively, and promoted significant regeneration of the gastric mucosa after ulcer induction denoting increased cell proliferation, which was confirmed by PCNA immunohistochemistry. HE treatment prevented the reduction of GSH levels and SOD activity after acetic acid-induced gastric lesions. In addition, HE (10mg/kg) inhibited the MPO activity in acetic acid-induced gastric ulcers. CONCLUSIONS: The results of the present study indicate that the antioxidant properties of HE may contribute to the gastroprotective activity of this extract.


Assuntos
Achillea/química , Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Etanol/química , Extratos Vegetais/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Glutationa/metabolismo , Imuno-Histoquímica , Peroxidase/metabolismo , Ratos , Ratos Wistar , Úlcera Gástrica/prevenção & controle , Superóxido Dismutase/metabolismo
10.
J Ethnopharmacol ; 122(3): 468-72, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19429314

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Pfaffia glomerata (Spreng) Pedersen (Amaranthaceae) is a medicinal plant known in Brazil as "Paratudo" and "Brazilian ginseng" and is commonly used as tonic, antidiabetic and to treat gastric disorders. AIM OF THE STUDY: This study evaluates the possible mechanism by which hydroalcoholic extract (HE) of Pfaffia glomerata exerts its antinociceptive effect. MATERIALS AND METHODS: The HE was evaluated in acetic acid and glutamate models of pain or by biting behavior following intrathecal (i.t.) administration of agonists of excitatory aminoacids (EAA) receptors glutamate and pro-inflammatory cytokines, IL-1beta and TNF-alpha in mice. RESULTS: Oral administration of HE produced dose-dependent inhibition of acetic acid-induced visceral pain and glutamate-induced pain, with ID(50) of 64.6 (47.7-87.5)mg/kg and ID(50) of 370.8 (253.4-542.7)mg/kg, respectively. The HE (300 mg/kg, p.o.) antinociception, in the acetic acid test, was not affected by i.p. treatment of animals with naloxone. In addition, HE (300 mg/kg, p.o.) inhibited the pain-related behaviors induced by i.t. injection of trans-ACPD and TNF-alpha, but not by NMDA, AMPA, kainate or IL-1beta. CONCLUSIONS: Our results suggest that inhibition of glutamatergic metabotropic receptors and TNF-alpha may account for the antinociceptive action reported for the HE in models of chemical pain used in this study.


Assuntos
Amaranthaceae , Analgésicos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Dor/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Ácido Acético , Analgésicos/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Cicloleucina , Modelos Animais de Doenças , Agonistas de Aminoácidos Excitatórios , Feminino , Ácido Glutâmico/metabolismo , Injeções Espinhais , Interleucina-1beta , Camundongos , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Dor/induzido quimicamente , Dor/metabolismo , Extratos Vegetais/uso terapêutico , Raízes de Plantas , Fator de Necrose Tumoral alfa/antagonistas & inibidores
11.
Basic Clin Pharmacol Toxicol ; 104(4): 285-92, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19281601

RESUMO

The present study assessed the possible antinociceptive action of the hydroalcoholic extract, fractions and pure compounds obtained from the aerial parts of Baccharis illinita DC (Asteraceae) in behavioural models of chemical nociception in mice. The hydroalcoholic extract and fractions (hexane and aqueous but not EtOAc fraction) obtained from B. illinita (30-1000 mg/kg orally) produced a dose-related inhibition of the acetic acid-induced nociceptive response. However, the hexane fraction was more potent than the hydroalcoholic extract and the aqueous fraction. The hexane fraction derivatives baurenol, alpha-spinasterol and oleanolic acid (0.00001-10 mg/kg intraperitoneally) also caused potent inhibition of acetic acid-induced pain. The hexane fraction (300-1000 mg/kg orally) produced inhibition of both phases of formalin-induced pain. Moreover, the hexane fraction (30-600 mg/kg orally) also caused a dose-dependent inhibition of glutamate-induced pain. Nevertheless, the hexane fraction only at the dose of 300 mg/kg orally, produced partial inhibition of the paw oedema caused by carrageenan. Furthermore, the hexane fraction (300 mg/kg orally) caused inhibition of the nociceptive response induced by intrathecal injection of N-methyl-d-aspartic acid, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, tumour necrosis factor-alpha and interleukin-1beta. In contrast, the hexane fraction did not affect the biting response induced by the metabotropic or ionotropic glutamatergic receptor agonist (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid and kainate, respectively. In addition, the antinociception caused by the hexane fraction (300 mg/kg orally) in the acetic acid test was not affected by intraperitoneal treatment of mice with naloxone (a non-selective opioid receptor antagonist). The precise mechanism responsible for the antinociceptive effect of the hexane fraction remains unclear, but appears to be partly associated with an inhibition of glutamatergic transmission and an inhibition of pathways dependent on pro-inflammatory cytokines. Finally, baurenol, alpha-spinasterol and oleanolic acid have an important role in the antinociceptive effects of the hexane fraction. Moreover, the antinociceptive action demonstrated in the present study supports the ethnomedical uses of this plant.


Assuntos
Analgésicos/farmacologia , Baccharis/química , Dor/tratamento farmacológico , Extratos Vegetais/farmacologia , Analgésicos/administração & dosagem , Analgésicos/isolamento & purificação , Animais , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Camundongos , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Medição da Dor , Componentes Aéreos da Planta , Extratos Vegetais/administração & dosagem , Receptores de Glutamato , Solventes/química , Estigmasterol/administração & dosagem , Estigmasterol/análogos & derivados , Estigmasterol/isolamento & purificação , Estigmasterol/farmacologia , Triterpenos/administração & dosagem , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
12.
Fitoterapia ; 80(7): 421-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19481590

RESUMO

The gastrointestinal activity of hydroalcoholic extract (HE) of Salvia officinalis was evaluated in a model of ethanol-induced gastric lesion. HE showed excellent activity, with ID(50) 84.0 (54.8-128.9) mg/kg. The acetic acid-induced ulcer and the total acidity of the gastric secretion were also reduced by HE, and, in vitro experiments, the H(+),K(+)-ATPase activity was inhibited. Carnosol was identified as a possible active constituent for the gastroprotective effect of HE.


Assuntos
Abietanos/uso terapêutico , Antiulcerosos/uso terapêutico , Mucosa Gástrica/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/uso terapêutico , Salvia officinalis/química , Úlcera Gástrica/tratamento farmacológico , Abietanos/isolamento & purificação , Abietanos/farmacologia , Ácido Acético , Animais , Antiulcerosos/isolamento & purificação , Antiulcerosos/farmacologia , Etanol , Feminino , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta , Inibidores da Bomba de Prótons , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente
13.
J Ethnopharmacol ; 123(3): 385-91, 2009 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-19501270

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Maytenus ilicifolia Mart. ex. Reissek (Celastraceae) is widely used in Brazilian folk medicine to treat gastric disturbances. AIM OF THE STUDY: This work intended to characterize the effects of Maytenus ilicifolia on gastrointestinal motility. MATERIALS AND METHODS: Gastric emptying and intestinal transit were measured in the same animal. Mice received a semisolid marked with phenol red, half an hour after treatment with extracts. The amount of marker in the stomach and the distance reached in the intestine after 15 min were measured as index of gastrointestinal emptying and intestinal transit, respectively. RESULTS: Intraperitoneal administration of a flavonoid-rich extract potently reduced the gastric emptying (ED(50)=89 mg/kg) and the intestinal transit (ED(50)=31 mg/kg) of mice. Bio-guided purification of the flavonoid-rich extract by chemical partition with solvents of decreasing polarity yielded fraction insF with about 12-14 times higher activity than the initial flavonoid extract in both the gastric emptying and the intestinal transit. The inhibitory effects of the insF (9.7 mg/kg, i.p.) on gastric emptying and intestinal transit were reversed by co-administration of bethanechol (10 mg/kg, s.c.) but not by co-administration of metoclopramide (30 mg/kg, p.o.) indicating muscarinic but not dopaminergic interaction of the compounds of Maytenus. Chemical investigation of the insF fraction by HPLC-MS allowed the identification of 4 free flavonoids (catechin, epicatechin, quercetin and kaempferol), 29 flavonol glycosides and 8 tannins. The flavonol glycosides ranged from 1 to 4 monosaccharide units, having mainly quercetin and kaempferol as aglycone moieties, and the tannins were composed by catechin/epicatechin and/or afzelechin/epiafzelechin. CONCLUSIONS: Overall, the results indicate that the components of Maytenus ilicifolia have a potential use in the treatment of gastrointestinal motility disturbances such as diarrhea.


Assuntos
Colinérgicos/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Maytenus , Extratos Vegetais/farmacologia , Animais , Betanecol/farmacologia , Colinérgicos/administração & dosagem , Colinérgicos/química , Feminino , Flavonoides/farmacologia , Flavonóis/farmacologia , Glicosídeos/farmacologia , Injeções Intraperitoneais , Maytenus/química , Camundongos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Taninos/farmacologia
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