RESUMO
A new method based on Ultraviolet spectrophotometry was developed and compared with that based on high-performance liquid chromatography for the determination and quantification of anthraquinones in the extracts of Rhamnus purshiana bark. A validated quantitative analysis of cascaroside A, cascaroside B, emodin, and aloe-emodin in these herbal products has been previously performed using high-performance liquid chromatography coupled with a diode array detector. In the high-performance liquid chromatography analysis, all the anthraquinones showed satisfactory regression (r2 > 0.98) within the test ranges, and the recovery was in the range of 94-117%. The limits of detection and quantification were 0.008-0.010 and 0.029-0.035 µg/mL, respectively. Hierarchical cluster analysis and principal component analysis showed differences in the anthraquinones determined from herbal samples. Subsequently, a simple and low-cost ultraviolet spectrophotometric methodology for the quantitative analysis of the same compounds in the extracts was applied, and all the contents were determined. A paired t-test confirmed that there were no significant differences between the two methods. Our results revealed that the developed method is simple and provides the ability to discriminate and control the quality of anthraquinones in herbal products.
Assuntos
Emodina , Rhamnus , Antraquinonas/química , Cromatografia Líquida de Alta Pressão/métodos , Emodina/análise , Rhamnus/química , Espectrofotometria UltravioletaRESUMO
Oligodendrocytes produce the myelin that is critical for rapid neuronal transmission in the central nervous system (CNS). Disruption of myelin has devastating effects on CNS function, as in the demyelinating disease multiple sclerosis (MS). Microglia are the endogenous immune cells of the CNS and play a central role in demyelination and repair. There is a need for new potential therapies that regulate myelination and microglia to promote repair. Agathisflavone (FAB) is a non-toxic flavonoid that is known for its anti-inflammatory and neuroprotective properties. Here, we examined the effects of FAB (5-50 µM) on myelination and microglia in organotypic cerebellar slices prepared from P10-P12 Sox10-EGFP and Plp1-DsRed transgenic mice. Immunofluorescence labeling for myelin basic protein (MBP) and neurofilament (NF) demonstrates that FAB significantly increased the proportion of MBP + /NF + axons but did not affect the overall number of oligodendroglia or axons, or the expression of oligodendroglial proteins CNPase and MBP. FAB is known to be a phytoestrogen, but blockade of α- or ß- estrogen receptors (ER) indicated the myelination promoting effects of FAB were not mediated by ER. Examination of microglial responses by Iba1 immunohistochemistry demonstrated that FAB markedly altered microglial morphology, characterized by smaller somata and reduced branching of their processes, consistent with a decreased state of activation, and increased Iba1 protein expression. The results provide evidence that FAB increases the extent of axonal coverage by MBP immunopositive oligodendroglial processes and has a modulatory effect upon microglial cells, which are important therapeutic strategies in multiple neuropathologies.
Assuntos
Animais , CamundongosRESUMO
Flavonoids have been suggested to protect dopaminergic neurons in Parkinson's disease based on studies that used exogenous neurotoxins. In this study, we tested the protective ability of agathisflavone in SH-SY5Y cells exposed to the endogenous neurotoxin aminochrome. The ability of aminochrome to induce loss of lysosome acidity is an important mechanism of its neurotoxicity. We demonstrated that the flavonoid inhibited cellular death and lysosomal dysfunction induced by aminochrome. In addition, we demonstrated that the protective effect of agathisflavone was suppressed by antagonists of estrogen receptors (ERα and ERß). These results suggest lysosomal protection and estrogen signaling as mechanisms involved in agathisflavone neuroprotection in a Parkinson's disease study model.
Assuntos
Biflavonoides/farmacologia , Morte Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Síndromes Neurotóxicas/tratamento farmacológico , Humanos , Neuroproteção/efeitos dos fármacos , Neurotoxinas/farmacologia , Doença de Parkinson/tratamento farmacológicoRESUMO
Traumatic brain injury (TBI) is a critical health problem worldwide, with a high incidence rate and potentially severe long-term consequences. Depending on the level of mechanical stress, astrocytes react with complex morphological and functional changes known as reactive astrogliosis. In cases of severe tissue injury, astrocytes proliferate in the area immediately adjacent to the lesion to form the glial scar, which is a major barrier to neuronal regeneration in the central nervous system. The flavonoid agathisflavone has been shown to have neuroprotective, neurogenic, and immunomodulatory effects and could have beneficial effects in situations of TBI. In this study, we investigated the effects of agathisflavone on modulating the responses of astrocytes and neurons to injury, using the in vitro scratch wound model of TBI in primary cultures of rat cerebral cortex. In control conditions, the scratch wound induced an astroglial injury response, characterized by upregulation of glial fibrillary acidic protein (GFAP) and hypertrophy, together with the reduction in proportion of neurons within the lesion site. Treatment with agathisflavone (1 µM) decreased astroglial GFAP expression and hypertrophy and induced an increase in the number of neurons and neurite outgrowth into the lesion site. Agathisflavone also induced increased expression of the neurotrophic factors NGF and GDNF, which are associated with the neuroprotective profile of glial cells. These results demonstrate that in an in vitro model of TBI, the flavonoid agathisflavone modulates the astrocytic injury response and glial scar formation, stimulating neural recomposition.
Assuntos
Astrócitos/efeitos dos fármacos , Biflavonoides/farmacologia , Biflavonoides/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Neurônios/efeitos dos fármacos , Animais , Astrócitos/fisiologia , Lesões Encefálicas Traumáticas/patologia , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Camundongos , Neurônios/fisiologia , Gravidez , Ratos , Ratos WistarRESUMO
Inflammation and oxidative stress are common aspects of most neurodegenerative diseases in the central nervous system. In this context, microglia and astrocytes are central to mediating the balance between neuroprotective and neurodestructive mechanisms. Flavonoids have potent anti-inflammatory and antioxidant properties. Here, we have examined the anti-inflammatory and neuroprotective potential of the flavonoid agathisflavone (FAB), which is derived from the Brazilian plant Poincianella pyramidalis, in in vitro models of neuroinflammation. Cocultures of neurons/glial cells were exposed to lipopolysaccharide (LPS, 1 µg/mL) or interleukin (IL)-1ß (10 ng/mL) for 24 h and treated with FAB (0.1 and 1 µM, 24 h). FAB displayed a significant neuroprotective effect, as measured by nitric oxide (NO) production, Fluoro-Jade B (FJ-B) staining, and immunocytochemistry (ICC) for the neuronal marker ß-tubulin and the cell death marker caspase-3, preserving neuronal soma and increasing neurite outgrowth. FAB significantly decreased the LPS-induced microglial proliferation, identified by ICC for Iba-1/bromodeoxyuridine (BrdU) and CD68 (microglia M1 profile marker). In contrast, FAB had no apparent effect on astrocytes, as determined by ICC for glial fibrillary acidic protein (GFAP). Furthermore, FAB protected against the cytodestructive and proinflammatory effects of IL-1ß, a key cytokine that is released by activated microglia and astrocytes, and ICC showed that combined treatment of FAB with α and ß estrogen receptor antagonists did not affect NF-κB expression. In addition, qPCR analysis demonstrated that FAB decreased the expression of proinflammatory molecules TNF-α, IL-1ß, and connexins CCL5 and CCL2, as well as increased the expression of the regulatory molecule IL-10. Together, these findings indicate that FAB has a significant neuroprotective and anti-inflammatory effect in vitro, which may be considered as an adjuvant for the treatment of neurodegenerative diseases.
Assuntos
Anti-Inflamatórios/farmacologia , Biflavonoides/farmacologia , Interleucina-1beta/farmacologia , Lipopolissacarídeos/farmacologia , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fitoestrógenos/farmacologia , Anti-Inflamatórios/uso terapêutico , Biflavonoides/uso terapêutico , Técnicas de Cocultura , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/patologia , Neuroglia/patologia , Neurônios/patologia , Fitoestrógenos/uso terapêuticoRESUMO
Flavonoids are bioactive compounds that are known to be neuroprotective against glutamate-mediated excitotoxicity, one of the major causes of neurodegeneration. The mechanisms underlying these effects are unresolved, but recent evidence indicates flavonoids may modulate estrogen signaling, which can delay the onset and ameliorate the severity of neurodegenerative disorders. Furthermore, the roles played by glial cells in the neuroprotective effects of flavonoids are poorly understood. The aim of this study was to investigate the effects of the flavonoid agathisflavone (FAB) in primary neuron-glial co-cultures from postnatal rat cerebral cortex. Compared to controls, treatment with FAB significantly increased the number of neuronal progenitors and mature neurons, without increasing astrocytes or microglia. These pro-neuronal effects of FAB were suppressed by antagonists of estrogen receptors (ERα and ERß). In addition, treatment with FAB significantly reduced cell death induced by glutamate and this was associated with reduced expression levels of pro-inflammatory (M1) microglial cytokines, including TNFα, IL1ß and IL6, which are associated with neurotoxicity, and increased expression of IL10 and Arginase 1, which are associated with anti-inflammatory (M2) neuroprotective microglia. We also observed that FAB increased neuroprotective trophic factors, such as BDNF, NGF, NT4 and GDNF. The neuroprotective effects of FAB were also associated with increased expression of glutamate regulatory proteins in astrocytes, namely glutamine synthetase (GS) and Excitatory Amino Acid Transporter 1 (EAAT1). These findings indicate that FAB acting via estrogen signaling stimulates production of neurons in vitro and enhances the neuroprotective properties of microglia and astrocytes to significantly ameliorate glutamate-mediated neurotoxicity.
Assuntos
Biflavonoides/farmacologia , Fabaceae , Ácido Glutâmico/efeitos adversos , Degeneração Neural/prevenção & controle , Neurogênese/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Biflavonoides/antagonistas & inibidores , Morte Celular/efeitos dos fármacos , Córtex Cerebral , Técnicas de Cocultura , Citocinas/metabolismo , Transportador 1 de Aminoácido Excitatório/metabolismo , Fabaceae/química , Glutamato-Amônia Ligase/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Degeneração Neural/induzido quimicamente , Fatores de Crescimento Neural/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Piperidinas/farmacologia , Cultura Primária de Células , Pirazóis/farmacologia , Pirimidinas/farmacologia , RatosRESUMO
Neoflavonoids, which are classified as 4-arylcoumarin (neoflavone), 3,4-dihydro-4-arylcoumarin and neoflavene, have been the subject of a number of studies with respect to their therapeutic potential and, despite promising in vitro, ex vivo and in vivo pharmacological activities, there is a lack of studies demonstrating their toxicological properties. Therefore, this study aims to evaluate the acute (14 days) and repeated-dose (28 days) toxicity of synthetic neoflavonoid 7-acetoxy-4-aryl-3,4-dihydrocoumarin in Swiss mice through parameters related to changes in body weight, food and water intake, hematological and biochemical parameters. Toxicity studies using acute doses (300 and 2000â¯mg/kg) and repeated doses (250, 500 and 1000â¯mg/kg) orally were carried out as per Organization for Economic Co-operation and Development (OECD) guidelines 423 and 407, respectively. Based on the results of this study, treatment with 7-acetoxy-4-aryl-3,4-dihydrocoumarin was found to not cause clinical adverse symptoms and mortality in any animal used in the acute and repeated-dose toxicity study. In addition, no significant changes were observed in body weight and internal organs, food and water intake, hematological and biochemical parameters, compared to control group. Therefore, these results provide an initial understanding regarding the toxicity profile of 7-acetoxy-4-aryl-3,4-dihydrocoumarin, which can be considered a neoflavonoid with toxicity seen at doses higher than 2000â¯mg/kg in Swiss mice.
Assuntos
Cumarínicos/toxicidade , Animais , Artemia/efeitos dos fármacos , Feminino , Masculino , Camundongos , Testes de Toxicidade Aguda , Testes de Toxicidade SubagudaRESUMO
The present study assessed the in vivo anthelmintic activity of the C. mollis leaf decoction extract when administered orally to naturally infected goats with gastrointestinal nematodes. To this, animals were randomized into three groups:non-treated, control (treated with doramectin 1mL/50 kg b.w.) and C. mollis extract treated groups (2.5mg/kg b.w.). Blood and faecal samples were collected from each animal at day 0, and 30th day post-treatment to monitor immunological and parasitological parameters. A significant faecal egg reduction (61.1%) and an increase in IgA and eosinophils levels were observed in the C. mollis extract treated group, in comparison to the untreated and doramectin groups. Considering that gastrointestinal nematode infections in small ruminants are serious problems in the world, causing economic losses worldwide, associated to high anthelmintic cost, resistance to available anthelmintics and residue problems in meat and milk for human consumption, the plant extract use is an area of interest to search new anthelmintic agents. Thus, Cratyliamollis Mart. Ex Benth, an important medicinal plant from Brazilian Northeast semi-arid region, is used to treat different types of diseases, and as forage supplementation.
Este estudo avaliou a capacidade anti-helmíntica in vivo do extrato aquoso de folhas de C. mollis, administrado por via oral em caprinos naturalmente infectados com nematódeos gastrintestinais. Para isto, os animais foram aleatoriamente distribuídos em três grupos (grupo não tratado, grupo controle tratado com doramectina (1mL/50 kg de peso corpóreo) e grupo tratado com o extrato aquoso de C. mollis (2,5mg/ kg de peso corpóreo). Amostras de sangue e fezes foram colhidas de cada animal nos dias 0 e 30 após o tratamento para verificar parâmetros imunológicos e parasitológicos. Uma redução significativa na oviposição (61,1%) e um aumento dos níveis de IgA e eosinófilos foram observados no grupo tratado com o extrato aquoso, em comparação aos grupos controle (não tratado e tratado com doramectina). Considerando que nematódeos gastrintestinais de pequenos ruminantes causam perdas econômicas ao nível mundial, devido ao custo e à resistência aos antihelmínticos disponíveis, além do efeito residual nos derivados animais para consumo humano, os extratos vegetais apresentam-se como uma fonte alternativa de anti-helmínticos. Assim, Cratyliamollis Mart. ExBenth é uma planta usada no semi-áridodo Nordeste brasileiro para tratardoenças e como forragem.
Assuntos
Animais , Nematoides/classificação , Nematoides/parasitologia , Ruminantes/parasitologia , Imunidade nas MucosasRESUMO
The present study assessed the in vivo anthelmintic activity of the C. mollis leaf decoction extract when administered orally to naturally infected goats with gastrointestinal nematodes. To this, animals were randomized into three groups:non-treated, control (treated with doramectin 1mL/50 kg b.w.) and C. mollis extract treated groups (2.5mg/kg b.w.). Blood and faecal samples were collected from each animal at day 0, and 30th day post-treatment to monitor immunological and parasitological parameters. A significant faecal egg reduction (61.1%) and an increase in IgA and eosinophils levels were observed in the C. mollis extract treated group, in comparison to the untreated and doramectin groups. Considering that gastrointestinal nematode infections in small ruminants are serious problems in the world, causing economic losses worldwide, associated to high anthelmintic cost, resistance to available anthelmintics and residue problems in meat and milk for human consumption, the plant extract use is an area of interest to search new anthelmintic agents. Thus, Cratyliamollis Mart. Ex Benth, an important medicinal plant from Brazilian Northeast semi-arid region, is used to treat different types of diseases, and as forage supplementation.(AU)
Este estudo avaliou a capacidade anti-helmíntica in vivo do extrato aquoso de folhas de C. mollis, administrado por via oral em caprinos naturalmente infectados com nematódeos gastrintestinais. Para isto, os animais foram aleatoriamente distribuídos em três grupos (grupo não tratado, grupo controle tratado com doramectina (1mL/50 kg de peso corpóreo) e grupo tratado com o extrato aquoso de C. mollis (2,5mg/ kg de peso corpóreo). Amostras de sangue e fezes foram colhidas de cada animal nos dias 0 e 30 após o tratamento para verificar parâmetros imunológicos e parasitológicos. Uma redução significativa na oviposição (61,1%) e um aumento dos níveis de IgA e eosinófilos foram observados no grupo tratado com o extrato aquoso, em comparação aos grupos controle (não tratado e tratado com doramectina). Considerando que nematódeos gastrintestinais de pequenos ruminantes causam perdas econômicas ao nível mundial, devido ao custo e à resistência aos antihelmínticos disponíveis, além do efeito residual nos derivados animais para consumo humano, os extratos vegetais apresentam-se como uma fonte alternativa de anti-helmínticos. Assim, Cratyliamollis Mart. ExBenth é uma planta usada no semi-áridodo Nordeste brasileiro para tratardoenças e como forragem.(AU)
Assuntos
Animais , Ruminantes/parasitologia , Nematoides/classificação , Nematoides/parasitologia , Imunidade nas MucosasRESUMO
CONTEXT: The labdenic diterpene labd-8(17)-en-15-oic acid (labd-8) isolated from a methanolic extract of Moldenhawera nutans Queiroz & Alkin (Leguminosae) has hypotensive and tachycardiac properties in normotensive rats. A part of the hypotensive effect was due to a reduction in the sympathetic nerve drive to vessels, an event admittedly enhanced in spontaneously hypertensive rats (SHRs). OBJECTIVES: We assessed whether the cardiovascular effects induced by labd-8 could be enhanced in SHRs. MATERIALS AND METHODS: For in vivo experiments, arterial and venous catheters were implanted under anesthesia for blood pressure recording and drug administration, respectively. For in vitro experiments, thoracic aorta rings were suspended in organ baths containing warm (37 °C) perfusion medium that was continuously bubbled with carbogen. RESULTS: Intravenous injection of labd-8 (1, 3, 5, and 10 mg/kg) induced similar dose-dependent hypotension and tachycardia in both SHRs and Wistar-Kyoto rats (WKY). In SHRs, only the tachycardia response to labd-8 was significantly reduced by pretreatment with methylatropine or propranolol. However, both cardiovascular effects of labd-8 were reduced by hexamethonium while remained unchanged by l-NAME. In isolated aortic preparations from SHRs, labd-8 (1-1000 µg/mL) relaxed potassium-induced contractions with an IC50 (geometric mean [95% confidence interval]) value (536.5 [441.0-631.9] µg/mL) significantly greater than that (157.6 [99.1-250.5] µg/mL) obtained in preparations from WKY rats. CONCLUSION: In SHRs, the hypotension induced by labd-8 is associated with a reflex tachycardia and seems mediated partly through withdrawal of sympathetic vasomotor tone and partly through an active vasorelaxation. Its magnitude was not enhanced when compared with WKY rats likely because of impaired vasorelaxant effects of labd-8 in preparations from SHRs.