RESUMO
Stingless bees, or simply meliponines, are a large group of bees (about 550 described species), comprising the tribe Meliponini. They belong in the family Apidae, and are closely related to Apis mellifera. Scaptotrigona affinis postica Latreille, 1807 from northeast of Brazil is popularly known as “tubi” in Maranhão State. Flavones di-C-glycosides, and the pyrrolizidine alkaloid 3-methoxy-7-(2-methylbutyryl)-9-echimidinyl retronecine (7) were reported previously in propolis from S. postica and detected only in samples collected in October, November and December. The presence of pyrrolizidine alkaloids and their N-oxides were reported in honey and pollen. In the present study, the preparative liquid chromatography in reversed-phase column from ethanolic extract of propolis allowed the separation of fractions 40AEP and 40 MEP, which were analyzed by LC-MS. Many pyrrolizidine alkaloids, among them, lithosenine (14), lithosenine arabinoside (19), 7-angeloyl-9-(2,3- dihydroxybutyryl) retronecine (1), 7-(2- methylbutyryl) retronecine (3), 9-sarracinoyl retronecine (13) and viridinatine (8), besides the flavonoids schaftoside (15), aromadendrin-7-O-methyl ether (12), 7- methoxy-5,6,3’,4’,5’,6’-hexahydroxy-flavone-3-O-glucuronide (11), mangiferin (10) and mangiferin-O-methyl ether (17) were detected in these fractions. Fraction 40MEP showed antibacterial effect against gram positive and gram negative bacterial pathogens with MIC ranging from 62.5 μg/mL to 200 μg/mL, while fractions 40AEP and 40MEP showed antimicrobial activity against gram negative bacteria, including Escherichia coli D31- streptomycin resistant. The cells were treated with 40MEP and 40AEP at a concentration of 200 μg/mL and were not observed statistical difference between treated and untreated cells.
RESUMO
The studies on chemical composition and biological activity of propolis had focused mainly on species Apis mellifera L. (Hymenoptera: Apidae). There are few studies about the uncommon propolis collected by stingless bees of the Meliponini tribe known as geopropolis. The geopropolis from Scaptotrigona postica was collected in the region of Barra do Corda, Maranhão state, Brazil. The chemical analysis of hydromethanolic extract of this geopropolis (HMG) was carried out through HPLC-DAD-ESI-MS/MS and the main constituents found were pyrrolizidine alkaloids and C-glycosyl flavones. The presence of alkaloids in extracts of propolis is detected for the first time in this sample. The antiviral activity of HMG was evaluated through viral DNA quantification experiments and electron microscopy experiments. Quantification of viral DNA from herpes virus showed reduction of about 98% in all conditions and concentration tested of the HMG extract. The results obtained were corroborated by transmission electron microscopy, in which the images did not show particle or viral replication complex. The antiviral activity of C-glycosyl flavones was reported for a variety of viruses, being observed at different points in the viral replication. This work is the first report about the antiviral activity of geopropolis from Scaptotrigona postica, in vitro, against antiherpes simplex virus (HSV).
Assuntos
Vírus , Abelhas , QuímicaRESUMO
Propolis is a complex honeybee product with resinous aspect, containing plant exudates and beeswax. Their color, texture, and chemical composition vary, depending on the location of the hives and local flora. The most studied Brazilian propolis is the green (alecrim-do-campo) type, which contains mainly prenylated phenylpropanoids and caffeoylquinic acids. Other types of propolis are produced in Brazil, some with red color, others brown, grey, or black. The aim of the present work was to determine the chemical profiles of alcohol and chloroform extracts of eight samples of propolis, corresponding to six Brazilian regions. Methanol and chloroform extracts were obtained and analyzed by HPLC/DAD/ESI/MS and GC/MS. Two chemical profiles were recognized among the samples analyzed: (1) black Brazilian propolis, characterized chiefly by flavanones and glycosyl flavones, stemming from Picos (Piauí state) and Pirenópolis (Goiás state); (2) green Brazilian propolis, characterized by prenylated phenylpropanoids and caffeoylquinic acids, stemming from Cabo Verde (Bahia state), Lavras and Mira Bela (Minas Gerais state), Pariquera-Açu and Bauru (São Paulo state), and Ponta Grossa (Paraná state). The present work represents the first report of prenylated flavonoids in Brazilian propolis and schaftoside (apigenin-8-C-glucosyl-6-C-arabinose) in green propolis.
RESUMO
Tilia species, among which is Tilia cordata Mill. (Tiliaceae), have been used in folk medicine as anxiolytic. The hydroethanolic extract was analyzed by using liquid chromatography with mass spectrometry HPLC-DAD-ESI-MS/MS in negative ion mode, and its chemical composition was compared to flavonoids reported as anxiolytics. The major flavonoids found were: quercetin-3,7-di-O-rhamnoside, kaempferol-3,7-di-O-rhamnoside and kaempferol 3-O-(6"-p-coumaroyl glucoside) or tiliroside. The anxiolytic activity of the genus Tilia has been attributed to the presence of quercetin and kaempferol derivatives, while the anxiolytic activity of T. americana var. Mexicana was attributed to tiliroside, which was also found among the major constituents of this species.
As espécies de Tilia, entre elas, a Tilia cordata Mill. (Tiliaceae) são utilizadas como ansiolíticas na medicina popular. O extrato hidroalcoólico foi analisado usando cromatografia líquida acoplada à espectrometria de massas HPLC-DAD-ESI/MS/MS no modo negativo e a sua composição química foi comparada com os flavonóides já reportados como ansiolíticos. Os principais flavonóides encontrados foram: quercetina-3,7-di-O-rhamnosideo, canferol-3,7-di-O-rhamnosideo, e canferol 3-O-(6"-p-cumaroil glucosideo) ou tilirosideo. A atividade ansiolítica do gênero Tília tem sido atribuída à presença de derivados de canferol e quercetina, enquanto que a atividade ansiolítica da T. americana var. Mexicana foi atribuída ao tilirosideo, o qual também foi encontrado entre os principais constituintes desta espécie.
Assuntos
Ansiolíticos , Tilia europaea/análise , Quercetina , Glicosídeos , Cromatografia Gasosa-Espectrometria de Massas/métodosRESUMO
AIMS: To study if the course of cerulein-induced pancreatitis in rats changes in a state of triglyceride-rich lipoprotein metabolism alteration. METHODS: Two groups of rats received control diet during a 90-day period (A) and sucrose-rich diet to induce endogenous hypertriglyceridemia (B). Subgroups A2 and B2 received i.p. 45 microg cerulein/kg body weight (to induce acute pancreatitis). Histological examination of pancreas tissue, serum pancreatic lipase, lipoprotein profile and VLDL chemical composition were assessed. Then, pancreatic lipase hydrolytic activity on VLDL-triglycerides was evaluated in vitro. RESULTS: Cellular vacuolization was observed in all of the cerulein-injected rats, but only in subgroup B2 fat necrosis was present. Serum triglycerides were higher in subgroup B1 than in subgroup A1 (mean +/- SEM, mg/dl 123,77 +/- 25.7 vs. 65.8 +/- 7, p < 0.01). Triglycerides from rats fed with sucrose-rich diet, decreased after cerulein-induced pancreatitis (80.38 +/- 11.3 vs. 123,77 +/- 25.7, p < 0.02). Moreover, the endogenous hypertriglyceridemic rats showed an increment of VLDL triglyceride content, which decreased when rats were injected with cerulein. A negative correlation was found between VLDL-triglyceride content and serum pancreatic lipase activity (r = 0.58, p < 0.02). The in vitro assay showed a decrease in VLDL-triglyceride content post incubation with pancreatic lipase enriched serum (mean +/- SD: 59.2 +/- 27.7%, p < 0.01). CONCLUSIONS: The endogenous hypertriglyceridemia intensifies the course of cerulein-induced pancreatitis and it could be related to the decrease in VLDL-triglycerides as a consequence of pancreatic lipase hydrolytic activity.
Assuntos
VLDL-Colesterol/química , Hipertrigliceridemia/metabolismo , Lipase/metabolismo , Lipoproteínas VLDL/metabolismo , Pancreatite/metabolismo , Triglicerídeos/metabolismo , Doença Aguda , Animais , Ceruletídeo/toxicidade , VLDL-Colesterol/metabolismo , Lipase/sangue , Lipoproteínas VLDL/sangue , Masculino , Pancreatite/induzido quimicamente , Distribuição Aleatória , Ratos , Ratos Wistar , Triglicerídeos/sangueRESUMO
We have isolated from rat cerebral cortex an endogenous Na(+), K(+)-ATPase inhibitor, termed endobain E, which modulates glutamatergic N-methyl-d-aspartate (NMDA) receptor. This endogenous factor allosterically decreases [(3)H]dizocilpine binding to NMDA receptor, most likely acting as a weak channel blocker. In the present study we investigated whether endobain E is present in the cerebral cortex of rats subjected to ischemia and modulates NMDA receptor exposed to the same conditions. Ischemia-reperfusion was carried out by bilateral occlusion of common carotid arteries followed by a 15-min reperfusion period. Elution profile of brain soluble fraction showed that endobain E is present in cerebral cortex of ischemia-reperfusion rats. On assaying its effect on synaptosomal membrane Na(+), K(+)-ATPase activity and [(3)H]dizocilpine binding to cerebral cortex membranes prepared from animals without treatment, it was found that the endogenous modulator isolated from ischemia-reperfusion rats was able to inhibit both enzyme activity and ligand binding. On the other hand, endobain E prepared from rats without treatment also decreased binding to cerebral cortex or hippocampal membranes obtained from animals exposed to ischemia-reperfusion. Since ischemia decreases tissue pH and NMDA receptor activity varies according to proton concentration, pH influence on endobain E effect was tested. Endobain E ( approximately 80 mg original tissue) decreased [(3)H]dizocilpine binding 25% at pH 7.4 or 8.0 but 90% at pH 6.5. These results demonstrate that endobain E is present and also able to modulate NMDA receptor in the short-term period that follows cerebral ischemia and that its effect depends on proton concentration, suggesting greater NMDA receptor modulation by endobain E at low pH, typical of ischemic tissues.
Assuntos
Isquemia Encefálica/metabolismo , Córtex Cerebral/metabolismo , Ouabaína/análogos & derivados , Receptores de N-Metil-D-Aspartato/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Isquemia Encefálica/complicações , Isquemia Encefálica/enzimologia , Córtex Cerebral/enzimologia , Modelos Animais de Doenças , Maleato de Dizocilpina/metabolismo , Concentração de Íons de Hidrogênio , Membranas Intracelulares/enzimologia , Membranas Intracelulares/metabolismo , Masculino , Ouabaína/metabolismo , Ligação Proteica , Ratos , Ratos Wistar , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/etiologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Frações Subcelulares/enzimologia , Frações Subcelulares/metabolismoRESUMO
It has been demonstrated that the CNS is severely affected by hypoxic-ischemic insults during the prenatal-perinatal period, including imbalance in excitatory and inhibitory neurotransmitter release. Using a previously developed model of acute normobaric hypoxic hypoxia on chick embryos, we studied alterations observed both on [3H]GABA binding saturation parameters and on lactate concentration on successive embryonic days (ED). While maximal density of GABA binding sites (Bmax) from the low-affinity site was significantly reduced in an age-dependent manner, earlier stages of development (ED12 and 16) proving more vulnerable (ED12: control = 5.48 +/- 0.20, hypoxia = 3.90 +/- 0.39 pmol/mg prot, P < .05; ED16: control = 3.89 +/- 0.26, hypoxia = 2.80 +/- 0.28 pmol/mg prot, P < .05), ligand affinity (Kd) values and kinetic constants of the high-affinity site remained unaltered. Not unlikely, a physiological hypoxic state prevailing from ED17 up to hatching time rendered the whole embryo less sensitive to an externally induced hypoxic state (ED17: control = 2.93 +/- 0.06, hypoxia = 2.38 +/- 0.04 pmol/mg prot, P < .05; ED18: control = 2.97 +/- 0.12, hypoxia = 2.87 +/- 0.27 pmol/mg prot). Lactate levels in chick optic lobe homogenates were constant during development. The increase observed after hypoxic treatment compared to control value was significant at all stages studied, but increased percentage changes proved similar, indicating that all days of development equally perceive externally induced hypoxia. In conclusion, the present work demonstrates that after normobaric hypoxic hypoxia at different embryonic days, the embryo senses the externally induced hypoxic state as from ED12, but the GABA(A) receptor is differentially affected. It may be speculated that a different subunit composition of GABA(A) receptor is assembled in order to build a more stable receptor capable of resisting the physiological hypoxic state observed during the last few days before hatching.
Assuntos
Hipóxia-Isquemia Encefálica/metabolismo , Lobo Óptico de Animais não Mamíferos/metabolismo , Receptores de GABA-A/metabolismo , Animais , Embrião de Galinha , Lobo Óptico de Animais não Mamíferos/embriologia , Ligação Proteica , Ácido gama-Aminobutírico/metabolismoRESUMO
The present tests, in male Wistar rats, center around the trophic and functional changes of the pancreatic gland (R G), both exocrine and endocrine, induced by different types of autonomic nervous interruptions. First Group of Tests: Following one year celiac ganglionectomy (CG), nonpancreatectomized (Non-Pt) rats showed, basally, in blood, a drop of glucose (G), without changes of insulin (I). At autopsy, the CG animals showed an increase of the pancreatic we weight, of the total protein, of the RNA but not DNA. In the Pt. 95% rats, superimposing CG triggered, on the one hand, a drop to control values of the raised G blood levels, and on the other, a rise of I Besides, in feces, a rising of chymotrypsin concentration. At autopsy, in the PG, an increase of total protein and of RNA. Second Group of Tests: CG, after 6 months, induced, in blood, both basally and a 2 h glucose tolerance test, significant opposite enzyme activities changes in respect to C. Indeed, as amylase (A) was increased, that of lipase (L) was depressed. When alcohol feeding (AF) was superimposed to CG rats, a reversal of the L values was observed. The latter reached levels significantly higher those of the C. In in-vitro tests, the isolated islets of CG disclosed to release more I to the bath medium than those of the C animals. Third Group of Tests: Analyzing, in conscious animal, the L excretory changes in the basal bile pancreatic secretion (BB-PS) induced by chronic (2 months interruption of the autonomic nervous innervation of the PG, it was found that CG, truncal vagotomy (V), the association of CG + V, peri-Vaterian duodenotomy (PV-D), but not bilateral splachicectomy (Spl), inhibit, significantly the L output. It was also shown that superimosing AF to the V or CG + V animals reverted to C values the I depressed levels. In acute interruptions (24 h) of the autonomic nervous innervation of the PG: CG, V, P. V-D, the depression in the BBPS is highly significant, more than 40%. From these three sets of experiments it is concluded that: Firstly, CG increases the regenerative and functional capacity of both the exocrine pancreas. This is distinctively evident when the secretory mass is reduced like in the Pt. 95% series of animals. CG probably exerts its effects suppressing the releasing of some negative reins: adrenergic, pepdidergic (galanin). Secondly, CG evokes modifications of the normal Islet-pancreon inter-relationships. The rising of A and the drop of L in blood elicited by this type of autonomic nervous interruption probably reflects an increased release of I by the Langerhans islet. Thirdly, CG, the same as V. CG + V and P.V-D, but not Spl, depress the intrapancreatic cholinergic tone. This might by at the basis of the depression of L excretion in the BB-PS. The reversion to C Through the coupling of chronic alcohol intoxication to the autonomic decentralized PG would be a reflection of an increased sensitivity to ethanol of the intrapancreatic ganglionic neurons. The augmented acetylcholine release at the nerve terminal would lead to a high intrapancreatic cholinergic tone that, in the end, might be at the basis of the reversal changes induced in the autonomic decentralized PG by the chronic ethanol intoxication.
Assuntos
Denervação Autônoma , Sistema Nervoso Autônomo/fisiologia , Ganglionectomia , Pâncreas/fisiologia , Regeneração , Animais , Sistema Nervoso Autônomo/cirurgia , Plexo Celíaco/fisiologia , Plexo Celíaco/cirurgia , Etanol/toxicidade , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Lipase/metabolismo , Masculino , Pâncreas/inervação , Pâncreas/cirurgia , Pancreatectomia , Ratos , Ratos Wistar , VagotomiaRESUMO
Myeloperoxidase (MPO), a specific polymorphonuclear leukocyte enzyme, has been used previously to quantify the number of neutrophils in tissue. MPO activity was found to be linearly related to the number of neutrophil cells. In an attempt to use this method in leukocytes measuring in stool, fecal MPO was solubilized with hexadecyltrimethylammonium bromide and the MPO activity was measured by a dianisidine-H2O2 assay. Stools from 10 normal subjects and 39 patients with diarrhea produced by enteropathogenic bacteria were examined for leukocytes by MPO activity as well as microscopically using methylene blue stain, MPO activity was positive in 36 patients (92%) and leukocytes were present by microscopic observation in 30 (77%). Fecal leukocytes were not found in healthy controls and the MPO activity was undectable. Stool MPO activity had a range of from 1.6 to 2,830.0 x 10(3) UMPO per gram of feces (median 460.0). The number of neutrophils obtained through MPO activity had a range of 6.0 to 13,216.0/ mm3 (median 1,261.0). Fecal MPO activity is a simple biochemical assay for the detection and quantification of fecal leukocytes.
Assuntos
Diarreia/enzimologia , Fezes/enzimologia , Peroxidase/metabolismo , Diarreia/sangue , Fezes/citologia , Humanos , Contagem de Leucócitos , Leucócitos/enzimologia , Neutrófilos/enzimologiaRESUMO
En este estudio se presenta el caso de un paciente pediátrico que luego de ser sometido a un transplante hepático con donante vivo relacionado, presentó un cuadro de hiperfosfatasemia alcalina sérica. Se pone énfasis en la importancia de la utilización de la técnica de isoelectroenfoque para determinar el origen tisular del hallazgo mencionado