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The aim of this work was to identify the main chemical constituents and to evaluate the antilithiatic activity of the aqueous and hydroalcoholic extracts of stems of Caesalpinia bahamensis Lam. Fractionation and isolation of constituents from the hydroalcoholic extract was carried out by flash chromatography and semi-preparative liquid chromatography. The antilithiatic activity of the aqueous and hydroalcoholic extracts was evaluated in Wistar rats, where kidney stones were induced by ethylene glycol and ammonium chloride. Creatinine, calcium, and oxalate levels were evaluated and histological analysis was carried out. The homoisoflavonoids protosappanin B, 10-methyl-protosappanin B and brazilin were isolated and the antilithiatic activity of the aqueous and hydroalcoholic extracts was demonstrated by the reduction of the concentration of calcium and oxalate in urine compared to the lithiasis group. It was corroborated by histological analysis. Brazilin and protosappanin B were proposed as chemical markers for this plant species.
Assuntos
Caesalpinia , Animais , Caesalpinia/química , Cálcio , Oxalatos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos WistarRESUMO
In spite of the current advances and achievements in cancer treatments, colorectal cancer (CRC) persists as one of the most prevalent and deadly tumor types in both men and women worldwide. Drug resistance, adverse side effects and high rate of angiogenesis, metastasis and tumor relapse remain one of the greatest challenges in long-term management of CRC and urges need for new leads of anticancer drugs. We demonstrate that CRC treatment with the phytopharmaceutical mangiferin (MGF), a glucosylxanthone present in Mango tree stem bark and leaves (Mangifera Indica L.), induces dose-dependent tumor regression and decreases lung metastasis in a syngeneic immunocompetent allograft mouse model of murine CT26 colon carcinoma, which increases overall survival of mice. Antimetastatic and antiangiogenic MGF effects could be further validated in a wound healing in vitro model in human HT29 cells and in a matrigel plug implant mouse model. Interestingly, transcriptome pathway enrichment analysis demonstrates that MGF inhibits tumor growth, metastasis and angiogenesis by multi-targeting of mitochondrial oxidoreductase and fatty acid ß-oxidation metabolism, PPAR, SIRT, NFκB, Stat3, HIF, Wnt and GP6 signaling pathways. MGF effects on fatty acid ß-oxidation metabolism and carnitine palmitoyltransferase 1 (CPT1) protein expression could be further confirmed in vitro in human HT29 colon cells. In conclusion, antitumor, antiangiogenic and antimetastatic effects of MGF treatment hold promise to reduce adverse toxicity and to mitigate therapeutic outcome of colorectal cancer treatment by targeting mitochondrial energy metabolism in the tumor microenvironment.
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Marine plants have become an inexhaustible reservoir of new phytopharmaceuticals for cancer treatment. We demonstrate in vitro/in vivo antitumor efficacy of a standardized polyphenol extract from the marine angiosperm Thalassia testudinum (TTE) in colon tumor cell lines (RKO, SW480, and CT26) and a syngeneic allograft murine colorectal cancer model. MTT assays revealed a dose-dependent decrease of cell viability of RKO, CT26, and SW480 cells upon TTE treatment with IC50 values of, respectively, 175, 115, and 60 µg/mL. Furthermore, TTE significantly prevented basal and bFGF-induced angiogenesis in the chicken chorioallantoic membrane angiogenesis assay. In addition, TTE suppressed bFGF-induced migration of endothelial cells in a wound closure assay. Finally, TTE treatment abrogated CT26 colorectal cancer growth and increased overall organism survival in a syngeneic murine allograft model. Corresponding transcriptome profiling and pathway analysis allowed for the identification of the mechanism of action for the antitumor effects of TTE. In line with our in vitro/in vivo results, TTE treatment triggers ATF4-P53-NFκB specific gene expression and autophagy stress pathways. This results in suppression of colon cancer cell growth, cell motility, and angiogenesis pathways in vitro and in addition promotes antitumor immunogenic cell death in vivo.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Hydrocharitaceae , Morte Celular Imunogênica/efeitos dos fármacos , Neovascularização Patológica/patologia , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Humanos , Hydrocharitaceae/química , Morte Celular Imunogênica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
The complexity of the ischemic cascade is based on the integrated crosstalk of every cell type in the neurovascular unit. Depending on the features of the ischemic insult, several cell death mechanisms are triggered, such as apoptosis, necroptosis, ferroptosis/oxytosis, ETosis or pyroptosis, leading to reactive astrogliosis. However, emerging evidence demonstrates a dual role for the immune system in stroke pathophysiology, where it exerts both detrimental and also beneficial functions. In this review, we discuss the relevance of several cell death modalities and the dual role of the immune system in stroke pathophysiology. We also provide an overview of some emerging immunomodulatory therapeutic strategies, amongst which saponins, which are promising candidates that exert multiple pharmacological effects.
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Osteoarthritis (OA) pain has been proposed to be a mixed pain state, because in some patients, central nervous system factors are superimposed upon the more traditional peripheral factors. In addition, a considerable amount of preclinical and clinical evidence has shown that, accompanying the central neuroplasticity changes and partially driven by a peripheral nociceptive input, a real neuropathic component occurs that are particularly linked to disease severity and progression. Hence, innovative strategies targeting neuroprotection and particularly neuroinflammation to prevent and treat OA pain could be introduced. Mangiferin (MG) is a glucosylxanthone that is broadly distributed in higher plants, such as Mangifera indica L. Previous studies have documented its analgesic, anti-inflammatory, antioxidant, neuroprotective, and immunomodulatory properties. In this paper, we propose its potential utility as a multitargeted compound for mixed OA pain, even in the context of multimodal pharmacotherapy. This hypothesis is supported by three main aspects: the cumulus of preclinical evidence around this xanthone, some preliminary clinical results using formulations containing MG in clinical musculoskeletal or neuropathic pain, and by speculations regarding its possible mechanism of action according to recent advances in OA pain knowledge.
Assuntos
Analgésicos/uso terapêutico , Mangifera/química , Neuralgia/tratamento farmacológico , Osteoartrite/complicações , Xantonas/uso terapêutico , Humanos , Hiperalgesia/etiologia , Neuralgia/etiologia , Neuralgia/prevenção & controle , Neuroproteção/efeitos dos fármacosRESUMO
Stroke is frequently associated with severe neurological decline and mortality, and its incidence is expected to increase due to aging population. The only available pharmacological treatment for cerebral ischemia is thrombolysis, with narrow therapeutic windows. Efforts aimed to identify new therapeutics are crucial. In this study, we look into plausible molecular and cellular targets for JM-20, a new hybrid molecule, against ischemic stroke in vivo. Male Wistar rats were subjected to 90 min middle cerebral artery occlusion (MCAO) following 23 h of reperfusion. Animals treated with 8 mg/kg JM-20 (p.o., 1 h after reperfusion) showed minimal neurological impairment and lower GABA and IL-1ß levels in CSF when compared to damaged rats that received vehicle. Immunocontent of pro-survival, phosphorylated Akt protein decreased in the cortex after 24 h as result of the ischemic insult, accompanied by decreased number of NeuN+ cells in the peri-infarct cortex, cornu ammonis 1 (CA1) and dentate gyrus (DG) areas. Widespread reactive astrogliosis in both cortex and hippocampus (CA1, CA3, and DG areas) was observed 24 h post-ischemia. JM-20 prevented the activated Akt reduction, neuronal death, and astrocytes reactivity throughout the brain. Overall, the results reinforce the pharmacological potential of JM-20 as neuroprotective agent and provide important evidences about its molecular and cellular targets in this model of cerebral ischemia.
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Astrócitos/patologia , Benzodiazepinas/uso terapêutico , Infarto Encefálico/tratamento farmacológico , Encéfalo/patologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Neurônios/patologia , Niacina/análogos & derivados , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Benzodiazepinas/farmacologia , Infarto Encefálico/líquido cefalorraquidiano , Infarto Encefálico/patologia , Região CA3 Hipocampal/efeitos dos fármacos , Região CA3 Hipocampal/metabolismo , Região CA3 Hipocampal/patologia , Morte Celular/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Giro Denteado/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/metabolismo , Gliose/patologia , Infarto da Artéria Cerebral Média/líquido cefalorraquidiano , Interleucina-10/líquido cefalorraquidiano , Interleucina-1beta/líquido cefalorraquidiano , Masculino , Neurônios/efeitos dos fármacos , Niacina/farmacologia , Niacina/uso terapêutico , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Resultado do Tratamento , Ácido gama-Aminobutírico/líquido cefalorraquidianoRESUMO
The present study reproduces chronic post-ischemia pain (CPIP), a model of complex regional pain syndrome type I (CRPS-I), in rats to examine the possible transient and long-term anti-allodynic effect of mangiferin (MG); as well as its potential beneficial interactions with some standard analgesic drugs and sympathetic-mediated vasoconstriction and vasodilator agents during the earlier stage of the pathology. A single dose of MG (50 and 100 mg/kg, p.o.) decreased mechanical allodynia 72 h post-ischemia-reperfusion (I/R). MG 100 mg/kg, i.p. (pre- vs. post-drug) increased von Frey thresholds in a yohimbine and naloxone-sensitive manner. Sub-effective doses of morphine, amitriptyline, prazosin, clonidine and a NO donor, SIN-1, in the presence of MG were found to be significantly anti-allodynic. A long-term anti-allodynic effect at 7 and 13 days post-I/R after repeated oral doses of MG (50 and 100 mg/kg) was also observed. Further, MG decreased spinal and muscle interleukin-1ß concentration and restored muscle redox status. These results indicate that MG has a transient and long-term anti-allodynic effect in CPIP rats that appears to be at least partially attributable to the opioid and α2 adrenergic receptors. Additionally, its anti-inflammatory and antioxidant mechanisms could also be implicated in this effect. The association of MG with sub-effective doses of these drugs enhances the anti-allodynic effect; however, an isobolographic analysis should be performed to define a functional interaction between them. These findings suggest the possible clinical use of MG in the treatment of CRPS-I in both early sympathetically maintained pain and long-term sympathetically independent pain.
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Free radicals are important mediators in a number of neurodegenerative diseases and molecules capable of scavenging reactive oxygen species (ROS) may be a feasible strategy for protecting neuronal cells. In this sense, polyphenols have been studied for their antioxidant effects, KM-34 (5-(3, 4-dydroxyl-benzylidene)-2, 2-dimethyl-1, 3-dioxane-4, 6-Dione) is a novel synthetic catechol with potential neuroprotective and antioxidant properties. We have assessed the antioxidant (as scavenging and iron-chelating compound) and neuroprotectant in vitro (in PC12 cell injury induced by H2O2, glutamate or FeSO4/AA) of KM-34. KM-34 was found to be a potent antioxidant, as shown by (i) inhibition of iron induced-brain lipid peroxidation, (ii) inhibition of 2-deoxyribose degradation, (iii) inhibition of superoxide radicals generation (IC50=11.04 µM) and (iv) inhibition of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical reduction (IC50=16.26 µM). The overall anti-oxidant action of KM-34 appears to be a combination of a direct reaction with free radicals and chelating the metal ions responsible for the production of ROS. Our work suggests that the antioxidant properties of KM-34 may provide future therapeutic approaches for neurodegenerative disorders.
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Antioxidantes/farmacologia , Catecóis/síntese química , Catecóis/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Sequestradores de Radicais Livres/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , RatosRESUMO
Two spirosteroid analogues were synthesized and evaluated for their in vitro neuroprotective activities in PC12 cells, against glutamate-induced excitotoxicity and mitochondrial damage in glucose deprivation conditions, as well as their anti-inflammatory potential in LPS/IFNγ-stimulated microglia primary cultures. We also evaluated the in vitro anti-excitotoxic and anti-inflammatory activities of natural and endogenous steroids. Our results show that the plant-derived steroid solasodine decreased PC12 glutamate-induced excitotoxicity, but not the cell death induced by mitochondrial damage and glucose deprivation. Among the two synthetic spirosteroid analogues, only the (25R)-5α-spirostan-3,6-one (S15) protected PC12 against ischemia-related in vitro models and inhibited NO production, as well as the release of IL-1ß by stimulated primary microglia. These findings provide further insights into the role of specific modifications of the A and B rings of sapogenins for their neuroprotective potential.
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Anti-Inflamatórios , Microglia/metabolismo , Fármacos Neuroprotetores , Compostos de Espiro , Esteroides , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Morte Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Feminino , Interleucina-1beta/biossíntese , Microglia/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico/biossíntese , Células PC12 , Ratos , Compostos de Espiro/síntese química , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Esteroides/síntese química , Esteroides/química , Esteroides/farmacologiaRESUMO
Cerebral ischemia is the third most common cause of death and a major cause of disability worldwide. Beyond a shortage of essential metabolites, ischemia triggers many interconnected pathophysiological events, including excitotoxicity, oxidative stress, inflammation and apoptosis. Here, we investigated the neuroprotective mechanisms of JM-20, a novel synthetic molecule, focusing on the phosphoinositide-3-kinase (PI3K)/Akt survival pathway and glial cell response as potential targets of JM-20. For this purpose, we used organotypic hippocampal slice cultures exposed to oxygen-glucose deprivation (OGD) to achieve ischemic/reperfusion damage in vitro. Treatment with JM-20 at 0.1 and 10 µM reduced PI incorporation (indicative of cell death) after OGD. OGD decreased the phosphorylation of Akt (pro-survival) and GSK 3ß (pro-apoptotic), resulting in respective inhibition and activation of these proteins. Treatment with JM20 prevented the reduced phosphorylation of these proteins after OGD, representing a shift from pro-apoptotic to pro-survival signaling. The OGD-induced activation of caspase-3 was also attenuated by JM-20 treatment at 10 µM. Moreover, in cultures treated with JM-20 and exposed to OGD conditioning, we observed a decrease in activated microglia, as well as a decrease in interleukin (IL)-1ß, IL-6 and tumor necrosis factor (TNF)-α release into the culture medium, while the level of the anti-inflammatory IL-10 increased. GFAP immunostaining and IB4 labeling showed that JM-20 treatment significantly augmented GFAP immunoreactivity after OGD, when compared with cultures exposed to OGD only, suggesting the activation of astroglial cells. Our results confirm that JM-20 has a strong neuroprotective effect against ischemic injury and suggest that the mechanisms involved in this effect may include the modulation of reactive astrogliosis, as well as neuroinflammation and the anti-apoptotic cell signaling pathway.
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Benzodiazepinas/farmacologia , Morte Celular/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Hipocampo/efeitos dos fármacos , Niacina/análogos & derivados , Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Animais Recém-Nascidos , Glucose/metabolismo , Glicogênio Sintase Quinase 3 beta , Hipocampo/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Niacina/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Ratos WistarRESUMO
JM-20 (3-ethoxycarbonyl-2-methyl-4-(2-nitrophenyl)-4,11-dihydro-1H-pyrido[2,3-b][1,5]benzodiazepine) is a novel benzodiazepine dihydropyridine hybrid molecule, which has been shown to be a neuroprotective agent in brain disorders involving glutamate receptors. However, the effect of JM-20 on the functionality of the glutamatergic system has not been investigated. In this study, by using different in vitro preparations, we investigated the effects of JM-20 on (i) rat brain synaptic vesicles (L-[(3)H]-glutamate uptake, proton gradient built-up and bafilomycin-sensitive H(+)-ATPase activity), (ii) rat brain synaptosomes (glutamate release) and (iii) primary cultures of rat cortical neurons, astrocytes and astrocyte-neuron co-cultures (L-[(3)H]-glutamate uptake and glutamate release). We observed here that JM-20 impairs H(+)-ATPase activity and consequently reduces vesicular glutamate uptake. This molecule also inhibits glutamate release from brain synaptosomes and markedly increases glutamate uptake in astrocytes alone, and co-cultured neurons and astrocytes. The impairment of vesicular glutamate uptake by inhibition of the H(+)-ATPase caused by JM-20 could decrease the amount of the transmitter stored in synaptic vesicles, increase the cytosolic levels of glutamate, and will thus down-regulate neurotransmitter release. Together, these results contribute to explain the anti-excitotoxic effect of JM-20 and its strong neuroprotective effect observed in different in vitro and in vivo models of brain ischemia.
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Benzodiazepinas/farmacologia , Encéfalo/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Neurônios/efeitos dos fármacos , Niacina/análogos & derivados , Vesículas Sinápticas/efeitos dos fármacos , Sinaptossomos/efeitos dos fármacos , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Células Cultivadas , Masculino , Neurônios/metabolismo , Niacina/farmacologia , Ratos , Ratos Wistar , Vesículas Sinápticas/metabolismo , Sinaptossomos/metabolismoRESUMO
INTRODUCCIÓN: la mangiferina posee diferentes propiedades farmacológicas, y otras están por ser investigadas, tal como su actividad antitumoral como agente adyuvante a la quimioterapia antineoplásica convencional en la terapia combinada. OBJETIVO: evaluar el efecto antiproliferativo de la mangiferina sola y combinada con concentraciones bajas de agentes quimioterapéuticos. MÉTODOS: las líneas celulares de carcinoma de colon de ratón CT26.WT y normal de ovario de hámster chino CHO-K1, se trataron con mangiferina en combinación con cisplatino y 5-fluorouracilo bajo diferentes esquemas de tratamiento (secuencial y simultáneo), a diferentes concentraciones y tiempos de incubación. La viabilidad celular se determinó por el ensayo de MTT. RESULTADOS: la mangiferina (1-200 µg/mL) no fue citotóxica para ambas líneas celulares. El cotratamiento secuencial con mangiferina (1-200 µg/mL) por 3 h y cisplatino a concentraciones no citotóxicas (1 µM y 5 µM) durante 72 h, mostró un incremento significativo de la muerte celular en CT26.WT, sin inducir incremento significativo de la muerte en células CHO-K1, a concentraciones bajas de ambos compuestos. En el caso de los cotratamientos con mangiferina y 5-fluorouracilo (0,1 µM y 0,5 µM), se incrementó significativamente la muerte celular en los cotratamientos simultáneo por 72 h y secuencial 5-fluorouracilo 72 h y mangiferina 24 h en células CT26.WT; pero solo en este último, no se incrementó significativamente la muerte celular en CHO-K1. CONCLUSIONES: la mangiferina en combinación con concentraciones bajas no citotóxicas de cisplatino y 5-fluorouracilo, promueve la muerte celular e incrementa la citotoxicidad de estos agentes quimioterapéuticos en las condiciones de experimentación realizadas(AU)
INTRODUCTION: mangiferin has several pharmacological properties, but others remain to be deeply explored, such as antitumor activity since it may serve as adjuvant agent in conventional antitumoral chemotherapy in a combined treatment. OBJECTIVE: to evaluate the antiproliferative effect of the use of mangiferin alone and in combination with low concentrations of chemotherapeutic agents. METHODS: the CT26.WT mouse colon carcinoma and the CHO-K1 hamster ovary normal cell lines were treated with mangiferin in combination with cisplatin and 5-fluorouracil in several treatment schedules (sequential and simultaneous), at different concentrations and incubation times. The cell viability was evaluated by MTT assay. RESULTS: mangiferin (1-200 µg/mL) was not cytotoxic in both cell lines. Mangiferin (1-200 µg/mL) for 3h plus cisplatin at not citotoxic concentrations (1 µM and 5 µM) for 72 h in sequential combined treatment showed a significant increase of cell death in CT26.WT, without inducing significant increase of cell death in CHO-K1 cells at low concentrations of both compounds. In the case of combined mangiferina and 5-fluorouracil (0,1 µM and 0,5 µM) treatments, cell death rose in a significant way in simultaneous combined treatments for 72 h whereas sequential combined therapy with 5-fluorouracil for 72 h plus mangiferin for 24 h in CT26.WT cells, a significant rise was not induced in the cell line death of CHO-K1 hamster CONCLUSIONS: mangiferin in combination with low non cytotoxic concentrations of cisplatin and 5-fluorouracil promotes cell death and increases the cytotoxicity of these chemotherapeutic agents in experimental conditions of this study(AU)
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Ratos , Protocolos de Quimioterapia Combinada Antineoplásica , /uso terapêutico , Cisplatino/uso terapêutico , Fluoruracila/uso terapêuticoRESUMO
Because mitochondrial oxidative stress and impairment are important mediators of neuronal damage in neurodegenerative diseases and in brain ischemia/reperfusion, in the present study, we evaluated the antioxidant and mitoprotective effect of a new promising neuroprotective molecule, JM-20, in mitochondria and synaptosomes isolated from rat brains. JM-20 inhibited succinate-mediated H2O2 generation in both mitochondria and synaptosomes incubated in depolarized (high K(+)) medium at extremely low micromolar concentration and with identical IC50 values of 0.91 µM. JM-20 also repressed glucose-induced H2O2 generation stimulated by rotenone or by antimycin A in synaptosomes incubated in high sodium-polarized medium at extremely low IC50 values of 0.395 µM and 2.452 µM, respectively. JM-20 was unable to react directly with H2O2 or with superoxide anion radicals but displayed a cathodic reduction peak at -0.71V, which is close to that of oxygen (-0.8V), indicating high electron affinity. JM-20 also inhibited uncoupled respiration in mitochondria or synaptosomes and was a more effective inhibitor in the presence of the respiratory substrates glutamate/malate than in the presence of succinate. JM-20 also prevented Ca(2+)-induced mitochondrial permeability transition pore opening, membrane potential dissipation and cytochrome c release, which are key pathogenic events during stroke. This molecule also prevented Ca(2+) influx into synaptosomes and mitochondria; the former effect was a consequence of the latter because JM-20 inhibition followed the patterns of carbonyl cyanide p-trifluoromethoxyphenyl hydrazone (FCCP), which is a classic mitochondrial uncoupler. Because the mitochondrion is considered an important source and target of neuronal cell death signaling after an ischemic insult, the antioxidant and protective effects of JM-20 against the deleterious effects of Ca(2+) observed at the mitochondrial level in this study may endow this molecule with the ability to succeed in mitochondrion-targeted strategies to combat ischemic brain damage.
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Antioxidantes/farmacologia , Benzodiazepinas/farmacologia , Cálcio/toxicidade , Mitocôndrias/efeitos dos fármacos , Niacina/análogos & derivados , Prosencéfalo/ultraestrutura , Sinaptossomos/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Catalase/farmacologia , Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Niacina/farmacologia , Oligomicinas/farmacologia , Oxigênio/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismoRESUMO
The present study examines the possible effect of the glucosylxanthone mangiferin (MG) on pain-related behaviors in a tonic acute pain model (formalin test at 5%) and in a chronic constriction injury (CCI) model to clarify the underlying transient and long-term mechanisms. Acute administration of MG (10-100mg/kg, i.p.) reduced licking/biting exclusivity in the tonic phase of formalin test in a naloxone and yohimbine-sensitive manner. This effect was enhanced by a nonselective nitric oxide synthase (NOS) inhibitor (NG-monomethyl-L-arginine) and by a non-competitive N-methyl-D-aspartate (NMDA) antagonist (ketamine), but it was reversed by the NOS substrate (L-arginine). Pre-treatment with intrathecal yohimbine prevented the anti-hypernociceptive effect of systemic MG. Pre-treatment during 4 days before surgical and 3 days after CCI with MG (50mg/kg, i.p.) reduced mechanical hypernociception and decreased the signs of Wallerian degeneration (WD) of the sciatic nerve. MG improved the PC-12 cellular viability exposure to glutamate-mediated neuronal death, also involved in neuropathic pain. The findings of this study suggest that MG shows ability to decrease tonic pain in the formalin test. A transient activity of this xanthone on nociceptive pathways mediated by α2 adrenergic receptors in cooperation with the opioid system could be involved, at least in part, in this effect. Its neuroprotective effect by preventing WD in mononeuropathic rats could be implicated in the mechano-antihypernociceptive long term mechanisms.
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Analgésicos/uso terapêutico , Modelos Animais de Doenças , Neuralgia/tratamento farmacológico , Xantonas/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Masculino , Células PC12 , Ratos , Ratos Sprague-Dawley , Xantonas/farmacologiaRESUMO
We previously showed that JM-20, a novel 1,5-benzodiazepine fused to a dihydropyridine moiety, possessed an anxiolytic profile similar to diazepam and strong neuroprotective activity in different cell models relevant to cerebral ischemia. Here, we investigated whether JM-20 protects against ischemic neuronal damage in vitro and in vivo. The effects of JM-20 were evaluated on hippocampal slices subjected to oxygen and glucose deprivation (OGD). For in vivo studies, Wistar rats were subjected 90 min of middle cerebral artery occlusion (MCAo) and oral administration of JM-20 at 2, 4 and 8 mg/kg 1 h following reperfusion. Twenty-four hours after cerebral blood flow restoration, neurological deficits were scored, and the infarct volume, histopathological changes in cortex, number of hippocampal and striatal neurons, and glutamate/aspartate concentrations in the cerebrospinal fluid were measured. Susceptibility to brain mitochondrial swelling, membrane potential dissipation, H2O2 generation, cytochrome c release, Ca2+ accumulation, and morphological changes in the organelles were assessed 24 h post-ischemia. In vitro, JM-20 (1 and 10 µM) administered during reperfusion significantly reduced cell death in hippocampal slices subjected to OGD. In vivo, JM-20 treatment (4 and 8 mg/kg) significantly decreased neurological deficit scores, edema formation, total infarct volumes and histological alterations in different brain regions. JM-20 treatment also protected brain mitochondria from ischemic damage, most likely by preventing Ca2+ accumulation in organelles. Moreover, an 8-mg/kg JM-20 dose reduced glutamate and aspartate concentrations in cerebrospinal fluid and the deleterious effects of MCAo even when delivered 8 h after blood flow restoration. These results suggest that in rats, JM-20 is a robust neuroprotective agent against ischemia/reperfusion injury with a wide therapeutic window. Our findings support the further examination of potential clinical JM-20 use to treat acute ischemic stroke.
Assuntos
Benzodiazepinas/farmacologia , Isquemia Encefálica/tratamento farmacológico , Aminoácidos Excitatórios/metabolismo , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Niacina/análogos & derivados , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Modelos Animais de Doenças , Glucose/deficiência , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Mitocôndrias/patologia , Mitocôndrias/fisiologia , Niacina/farmacologia , Distribuição Aleatória , Ratos Wistar , Técnicas de Cultura de TecidosRESUMO
This study aimed to assess the effects of a Mangifera indica stem bark extract (MSBE) and mangiferin (MG) on pain-related acute behaviors in the formalin 5% test. Rats received repeated oral MSBE (125-500 mg/kg) once daily for 7 days before formalin injection. Other four groups with the same treatments were performed in order to study the effect of MSBE on the formalin-induced long-term secondary mechano-hyperalgesia at 7 days after the injury by means of the pin-prick method. Additional groups received a single oral MSBE dose (250 mg/kg) plus ascorbic acid (1 mg/kg, i.p.). Also, repeated oral MG doses (12.5-50 mg/kg) during 7 days were administered. MSBE decreased licking/biting and flinching behaviors only in phase II and reduced the long-term formalin injury-induced secondary chronic mechano-hyperalgesia. The combination of MSBE plus ascorbic acid produced a reinforcement of this effect for flinching behavior, advising that antioxidant mechanisms are involved, at least in part, in these actions. Chronic administration of MG reproduced the effects of MSBE. For the first time, the antihyperalgesic effects of MSBE and MG in formalin 5% test, a recommended concentration for studying the antinociceptive activity of nitric oxide-related and N-methyl-d-aspartate-related compounds, were reported. These results could represent an important contribution to explain the analgesic ethnobotanical effects recognized to M. indica and other species containing MG.
Assuntos
Analgésicos/farmacologia , Hiperalgesia/tratamento farmacológico , Mangifera/química , Casca de Planta/química , Extratos Vegetais/farmacologia , Xantonas/farmacologia , Administração Oral , Animais , Masculino , Nociceptividade/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
The purpose of the present study was to evaluate the possible therapeutic effects and the safety of Mangifera indica extract (Vimang tablets, 300 mg) combined with methotrexate (MTX) on reducing disease activity in rheumatoid arthritis (RA). Twenty patients with active RA underwent a year of treatment with MTX (12.5 mg/week) associated to non-steroidal anti-inflammatory drugs (NSAIDs) and/or prednisone (5-10 mg/day) were randomly allocated to the experimental group (n=10), that received the extract supplementation (900 mg/day) or preceding usual treatment (n=10) during 180 days. RA activity was evaluated using the tender and swollen joint counts, erythrocyte sedimentation rate, disease activity score-28 (DAS 28), visual analogue scale (VAS) and health assessment questionnaire (HAQ). Treatment's efficacy was demonstrated with ACR criteria. Only the patients of MTX-Vimang group revealed statistically significant improvement in DAS 28 parameters with respect baseline data but no differences were observed between groups. ACR improvements amounted 80% only in MTX-Vimang group at the 90 days (p<0.001). In MTX-Vimang group, 100% of patients decreased NSAIDs administration (p<0.01) and 70% of those eradicated gastrointestinal side effects (p<0.01) ensuing of the preceding treatment. Other adverse effects were not reported.
Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Mangifera/química , Metotrexato/uso terapêutico , Extratos Vegetais/uso terapêutico , Adulto , Idoso , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do TratamentoRESUMO
Introducción: la diosgenina y sus derivados se han descrito como potentes inhibidores de la proliferación en varias líneas tumorales. Sin embargo otras moléculas relacionadas estructuralmente con dichos derivados, se han reportado como candidatos terapéuticos y otras de ellas se incluyen en alimentos de consumo humano. Objetivo: el presente trabajo evalúa el efecto sobre la viabilidad celular de una nueva serie de espiroesteroides sintéticos derivados de la diosgenina, en células tipo neurales PC12. Métodos: la viabilidad de los cultivos de PC12 se determinó mediante el ensayo de MTT y se calcularon descriptores moleculares teóricos como la lipofilicidad (logP virtual) y la superficie de área polar (SAP), con el objetivo de establecer relaciones estructura-actividad. Resultados: nuestros resultados demuestran que solo el acido taurodesoxicólico disminuye de manera significativa la viabilidad celular. Más aun, dicha molécula presenta valores menores y mayores de logP virtual y SAP, respectivamente, respecto al resto de los esteroides de la serie. Conclusiones: los resultados anteriores avalan el estudio del acido taurodesoxicólico como potencial inhibidor de la proliferación celular y al resto de las moléculas de la serie como candidatos neuroprotectores a evaluar en esta misma línea celular y dosis de tratamiento
Introduction: diosgenin and its derivatives have been described as potent anti-proliferative compounds in several tumor cell lines. However, other structurally-related compounds are reported to exert neuroprotective activity and are also included in food for human consumption. Objective: to evaluate the effect of a novel series of diogesin-derived synthetic spirosteroids on cellular viability of neuron-like PC12 cell line. Methods: cellular viability was determined by the MTT assay along with some theorical molecular descriptors, such as lipophilicity and polar surface area, in order to establish the structure-activity relationships. Results: the results demonstrated that only taurodeoxycholic acid significantly decrease PC12 cell culture viability. Moreover, this molecule presents lower virtual logP values and higher polar surface area values than the rest of spirosteroid series. Conclusions: those results endorse future studies of taurodeoxycholic acid as a potential anti-tumor candidate and of the rest of the molecules in this series as potential neuroprotective agents to be evaluated in this PC12 cell line and similar therapeutic dose
Assuntos
Sobrevivência Celular , Citotoxicidade Imunológica , Diosgenina/análogos & derivados , Ácido TaurodesoxicólicoRESUMO
Guttiferone-A (GA) is a natural occurring polyisoprenylated benzophenone with several reported pharmacological actions. We have assessed the protective action of GA on iron-induced neuronal cell damage by employing the PC12 cell line and primary culture of rat cortical neurons (PCRCN). A strong protection by GA, assessed by the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carbox-anilide (XTT) assay, was revealed, with IC(50) values <1 µM. GA also inhibited Fe(3+)-ascorbate reduction, iron-induced oxidative degradation of 2-deoxiribose, and iron-induced lipid peroxidation in rat brain homogenate, as well as stimulated oxygen consumption by Fe(2+) autoxidation. Absorption spectra and cyclic voltammograms of GA-Fe(2+)/Fe(3+) complexes suggest the formation of a transient charge transfer complex between Fe(2+) and GA, accelerating Fe(2+) oxidation. The more stable Fe(3+) complex with GA would be unable to participate in Fenton-Haber Weiss-type reactions and the propagation phase of lipid peroxidation. The results show a potential of GA against neuronal diseases associated with iron-induced oxidative stress.
Assuntos
Benzofenonas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Ascórbico/química , Ácido Ascórbico/toxicidade , Benzofenonas/química , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Desoxirribose/metabolismo , Embrião de Mamíferos , Compostos Férricos/química , Compostos Férricos/toxicidade , Quelantes de Ferro/química , Quelantes de Ferro/farmacologia , Cinética , Malondialdeído/metabolismo , Neurônios/metabolismo , Fármacos Neuroprotetores/química , Oxidantes/química , Oxidantes/toxicidade , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Ratos , Ratos WistarRESUMO
Overstimulation of ionotropic glutamate receptors causes excitotoxic neuronal death contributing to neurodegenerative disorders. Massive influx of calcium in excitotoxicity provokes alterations in the membrane potential of mitochondria and increases the production of reactive oxygen species. Here we report that Mangifera indica L. extracts (MiE) prevent glutamate-induced excitotoxicity in primary cultured neurons of the rat cerebral cortex. To evaluate the effects of MiE on excitotoxicity, cells were stimulated with L-glutamic acid (50 microM; 10 min) alone or in the presence of MiE. Maximal protection (56%) was obtained with 2.5 microg/mL of MiE. In turn, we measured the effects of MiE on excitotoxic-induced oxidative stress and mitochondrial depolarization by fluorimetry using 5,6-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate and tetramethylrhodamine, respectively. Both parameters were effectively reduced by MiE at concentrations which showed neuroprotection. Mangiferin, an antioxidant polyphenol which is a major component of MiE, was also effective in preventing neuronal death, oxidative stress and mitochondrial depolarization. Maximal protection (64%) was obtained at 12.5 microg/mL of mangiferin which also attenuated oxidative stress and mitochondrial depolarization at the neuroprotective concentrations. Together, these results indicate that MiE is an efficient neuroprotector of excitotoxic neuronal death, indicates that mangiferin carries a substantial part of the antioxidant and neuroprotective activity of MiE, and that this natural extract has therapeutic potential to treat neurodegenerative disorders.