RESUMO
One dimensional plasmonic grating is a kind of resonant electromagnetic wave absorber with a characteristic wavelength. This study focusses on one-dimensional plasmonic grating consisting of poly (glycidyl methacrylate) (PGMA) brushes and CdS quantum dots (CdQDs) fabrication and PGMA chains grafted on a primary substrate in a line array continued by the immobilization of biotin-modified CdQDs. PGMA brush line array (PBLA) of plasmonic grating exhibited an absorptance at 441 nm while at the same time, CdQDs immobilized with PBLA showed characteristic absorbance at 396 nm. The blue-shift from 441 nm matches the absorbance peak of biotin-modified CdQDs resulting in the enhancement of photoluminescence emission of CdQDs. With streptavidin incubation to assemble CdQDs at 50 nM, the significant decrease in grating height resulted in the red-shift of the absorbance peak to 536 nm. Due to the deviation in absorbance, the intensity of the PL emission decreased gradually with the increase in concentration of streptavidin. In addition, our results showed that streptavidin incubation altered the color reflected from the surface due to effective changes in the refractive index of the layer as well. The limit of detection of the grating for streptavidin detection was determined to be 50 nM. Thus, PBLA-CdQD has the potential to act as a highly-sensitive, label-free optical biosensor.
Assuntos
Técnicas Biossensoriais/métodos , Compostos de Cádmio/química , Ácidos Polimetacrílicos/química , Pontos Quânticos/química , Coloração e Rotulagem , Sulfetos/química , Biotina/química , Fenômenos Ópticos , Ressonância de Plasmônio de Superfície , Difração de Raios XRESUMO
The roots of Achyranthes bidentata Blume (AB) is commonly used in the treatment of osteoporosis and dementia in traditional Chinese medicine. Pharmacological reports evidenced that AB possessed anti-osteoarthritis effects. However, there is little literature about the anti-dementia activities of AB. The present study was designed to prepare steroid-enriched fraction of AB (ABS) and investigate whether ABS can protect from cognitive dysfunction and neuroinflammation against Aß 1-40-induced Alzheimer's disease (AD) model in rats. ABS only contained 135.11 ± 4.28 mg of ecdysterone per gram. ABS (50 mg/kg) reversed the dysfunction of exploratory activity and memory function on plus-maze and Morris water maze caused by Aß 1-40 in rats. ABS (50 mg/kg) also decreased amyloid deposition, neurofibrillary tangle, neural damage, activated astrocyte, and microglial caused by Aß 1-40. Furthermore, ABS reversed the phenomenon of neural oxidative damage and neuroinflammation, including the higher levels of MDA and cytokines, and the lower activities of antioxidant enzymes and GSH levels caused by Aß 1-40 in rat cortex and hippocampus. Finally, ABS restored the activation of ERK pathway and decreased NF-κB phosphorylation and translocation altered by Aß 1-40. ABS alone (50 mg/kg) promoted cognitive function, activated brain antioxidant defense system, and decreased brain TNF-α levels in sham group. Therefore, ABS has the cognition-promoting and antidementia potential. Steroids especial ecdysterone are major active components of AB. The action mechanism is due to decreasing oxidative stress and neuroinflammation through modulating ERK pathway, NF-κB phosphorylation, and translocation in Aß 1-40-induced AD rat model.
Assuntos
Achyranthes/química , Peptídeos beta-Amiloides/toxicidade , Encéfalo/patologia , Disfunção Cognitiva/tratamento farmacológico , Inflamação/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fragmentos de Peptídeos/toxicidade , Esteroides/uso terapêutico , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Comportamento Animal , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/fisiopatologia , Citocinas/metabolismo , Ecdisterona/análise , Glutationa/metabolismo , Hipocampo/enzimologia , Inflamação/complicações , Inflamação/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , NF-kappa B/metabolismo , Ácido Oleanólico/análise , Ratos Sprague-Dawley , Triterpenos/análise , Ácido UrsólicoRESUMO
OBJECTIVES: Diabetes mellitus (DM) is a widespread metabolic disorder worldwide. Clinical physicians have found diabetic patients have mild to middle cognitive dysfunction and an alteration of brain monoaminergic function. This study explored the change in various patterns of behavioral models and brain monoamine function under streptozotocin (STZ)-induced type 1 diabetes. MATERIALS AND METHODS: We established a type 1 DM model via intravenous injection with STZ (65 mg/kg) in rats. Three weeks after the STZ injection, various behavioral measurements including the inhibitory avoidance test, active avoidance test and Morris water maze were conducted. Finally, all rats were dissected and the concentrations of monoamines and their metabolites in cortex and hippocampus were measured by high performance liquid chromatography with electrochemical detection. RESULTS: We found that STZ induced type 1 diabetes (hyperglycemia and lack of insulin) in rats. STZ-induced diabetic rats had cognitive impairment in acquisition sessions and long-term retention of the active avoidance test. STZ-induced diabetic rats also had cognitive impairment in spatial learning, reference and working memory of the Morris water maze. STZ significantly reduced concentrations of norepinephrine (NE) in the cortex and dopamine (DA) in the hippocampus, but increased concentrations of DA and serotonin (5-HT) in the cortex 35 days after injection. The concentration of 5-HT in the hippocampus was also significantly increased. CONCLUSION: The data suggested that this cognitive impairment after a short-term period of STZ injection might be related to cortical NE dysfunction, differential alteration of cortical and hippocampal DA function, and brain 5-HT hyperfunction.
RESUMO
Antioxidant testing of natural products has attracted increasing interest in recent years, mainly due to the fact that an antioxidant-rich diet might provide health benefits. Activated macrophages are a major source of reactive oxygen species, reactive nitrogen species, and peroxynitrite generated through the so-called respiratory burst. Constitutively released proinflammatory cytokine, especially tumor necrosis factor-α, triggers nuclear factor-κB, and activator protein-1 translocation leading to the over production of reactive oxygen species and reactive nitrogen species in macrophages. Activation of transcription factors in the long-lived tissue-resident macrophages and/or monocyte-derived macrophages, trigger epigenetic modifications leading to the pathogenesis of chronic diseases. Nutraceuticals including lipid raft structure disruption agent, cholesterol depletion agent, farnesyltransferase inhibitor, nuclear factor-κB blocker (α,ß-unsaturated carbonyl compounds), glucocorticoid receptor agonist, and peroxisome proliferator-activated receptor-γ agonist have long been used to inactive macrophage. The inhibition effects on the formation of nitric oxide, superoxide, and nitrite peroxide may be responsible for the anti-inflammatory functionalities. Activated macrophage models could be used to identify the active components for functional diets development through a multiple targets strategy.
Assuntos
Estresse Oxidativo , Antioxidantes , Dieta , Macrófagos , Fator de Necrose Tumoral alfaRESUMO
Myricetin is a natural flavonol widely occurring in wines. Many beneficial effects of myricetin in alcoholic beverages have been reported before, but never including anti-obesity. In the present study, we fed obese male Sprague-Dawley rats with ethanol solutions containing various concentrations of myricetin and found that myricetin may maintain the food intake while reduce the weight-gain, feed efficiency, level of blood lipids, adipocyte size, and weight and size of the perirenal and epididymal adipose tissues (P < 0.01). Our experiment data also show that the anti-obesity effect may be associated with the upregulation of adropin and ß-endorphin levels. Based on the above-described findings, we propose the potential for myricetin-containing alcoholic beverages to be developed into anti-obesity health food.
Assuntos
Flavonoides/metabolismo , Obesidade/dietoterapia , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Bebidas Alcoólicas/análise , Animais , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Ingestão de Alimentos , Etanol/análise , Etanol/metabolismo , Humanos , Masculino , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Ratos , Ratos Sprague-Dawley , Aumento de PesoRESUMO
The Taiwanese native fern Davallia formosana Hayata (DFH) is used to treat bone diseases in classical Chinese medicine. We analyzed MC3T3E1 osteoblasts treated with different concentrations of water and ethanol extracts (10, 25, and 50 [both], and 100 µg/mL [DFE only]) using cell viability, expression of osteoblast differentiation markers [bone morphogenetic protein 2 (BMP-2), collagen 1 (CoL-1), alkaline phosphatase (ALP), and Runt-related transcription factor 2 (Runx 2)], and mineralization. These were significantly increased by DFW or DFE after 24-h incubation compared with the untreated controls. Compared with other treatments, DFW 50 and DFE 100 µg/mL significantly increased MC3T3E1 cell survival. DFW 25 and 50 µg/mL increased bone BMP-2, CoL-1, ALP, and Runx2 protein expression, ALP activity, and mineralization more than DFE did. Repeated chromatographic separation of DFW yielded compound (-)-epicatechin-3-O-d-allipyranoside (ECAP), which was characterized using 1 H and 13 C nuclear magnetic resonance spectroscopy. (-)-Epicatechin-3-O-d-allipyranoside (0.01 µg/mL) significantly increased cell survival (118.9%) and mineralization (218.7%) compared with that of the control treatment. We inferred that ECAP could mediate the main activity of DFW in bone formation, likely through BMP-2-induced Runx2 transcription, which increased bone cell differentiation factors ALP and CoL-1 and promoted mineralization. (-)-Epicatechin-3-O-d-allipyranoside could be an anti-osteoporotic agent. Copyright © 2017 John Wiley & Sons, Ltd.
Assuntos
Catequina/análogos & derivados , Gleiquênias/química , Glicosídeos/farmacologia , Osteoblastos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Células 3T3 , Fosfatase Alcalina/metabolismo , Animais , Proteína Morfogenética Óssea 2/metabolismo , Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Camundongos , Osteogênese/efeitos dos fármacosRESUMO
The present study provides in vitro and in vivo evaluation of arecoline on peripheral nerve regeneration. In the in vitro study, we found that arecoline at 50 µg/ml could significantly promote the survival and outgrowth of cultured Schwann cells as compared to the controls treated with culture medium only. In the in vivo study, we evaluated peripheral nerve regeneration across a 10-mm gap in the sciatic nerve of the rat, using a silicone rubber nerve chamber filled with the arecoline solution. In the control group, the chambers were filled with normal saline only. At the end of the fourth week, morphometric data revealed that the arecoline-treated group at 5 µg/ml significantly increased the number and the density of myelinated axons as compared to the controls. Immunohistochemical staining in the arecoline-treated animals at 5 µg/ml also showed their neural cells in the L4 and L5 dorsal root ganglia ipsilateral to the injury were strongly retrograde-labeled with fluorogold and lamina I-II regions in the dorsal horn ipsilateral to the injury were significantly calcitonin gene-related peptide-immunolabeled compared with the controls. In addition, we found that the number of macrophages recruited in the distal sciatic nerve was increased as the concentration of arecoline was increased. Electrophysiological measurements showed the arecoline-treated groups at 5 and 50 µg/ml had a relatively larger nerve conductive velocity of the evoked muscle action potentials compared to the controls. These results indicate that arecoline could stimulate local inflammatory conditions, improving the recovery of a severe peripheral nerve injury.
Assuntos
Arecolina/farmacologia , Agonistas Colinérgicos/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Traumatismos dos Nervos Periféricos , Nervo Isquiático/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Caspase 3/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/efeitos dos fármacos , Caspase 9/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocromos c/efeitos dos fármacos , Citocromos c/metabolismo , Fator de Crescimento Neural/efeitos dos fármacos , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Condução Nervosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Células de Schwann/efeitos dos fármacos , Nervo Isquiático/metabolismo , Proteína X Associada a bcl-2/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismoRESUMO
This study investigated the effect of ferulic acid (FA) on peripheral nerve injury. In the in vitro test, the effect of FA on viability of Schwann cells was studied. In the in vivo test, right sciatic nerves of the rats were transected, and a 15 mm nerve defect was created. A nerve conduit made of silicone rubber tube filled with FA (5 and 25 µg/mL), or saline (control), was implanted into the nerve defect. Results show that the number of proliferating Schwann cells increased significantly in the FA-treated group at 25 µg/mL compared to that in the control group. After 8 weeks, the FA-treated group at 25 µg/mL had a higher rate of successful regeneration across the wide gap, a significantly calcitonin gene-related peptide (CGRP) staining of the lamina I-II regions in the dorsal horn ipsilateral to the injury, a significantly diminished number of macrophages recruited, and a significantly shortening of the latency and an acceleration of the nerve conductive velocity (NCV) of the evoked muscle action potentials (MAPs) compared with the controls. In summary, the FA may be useful in the development of future strategies for the treatment of peripheral nerve injury.
RESUMO
BACKGROUND: Negative-pressure wound therapy (NPWT) is developed to facilitate wound healing at controlled subatmospheric pressures in modern medicine. Molecular mechanism for this therapy is still undefined. OBJECTIVE: This study highlights the localization and time-course of the cell division control protein 42 (Cdc42) in the cell membrane at ambient pressure (AP) and negative pressures of 75mmHg (NP75), 125mmHg (NP125) and 175mmHg (NP175). METHODS: The prepared cells were cultured in a negative pressure incubator with the same O2 and CO2 tensions at the four different pressures. The effective time, complete wound closure time, cell volume, cell viability, and the fluorescence of proliferating cell nuclear antigens (PCNA) and actins were evaluated in cells at different pressures. Wound-healing process and Cdc42 fluorescence were examined in cells with the knockdown of Cdc42. Cdc42 pathway proteins in cell membranes were analyzed after incubation at different pressures for 6 and 12h. RESULTS: The cells at NP125 had less wound closure time and obvious cell podia. Similar PCNA fluorescent intensity was observed in cells at different pressures. The Cdc42, neural Wiskott-Aldrich syndrome protein, and actin expression increased significantly (p<0.05) in plasma membranes of cells at NP125 for 12h. The knockdown of active Cdc42 resulted in the absence of Cdc42 expression at the cell leading edge. CONCLUSIONS: The activation and localization of Cdc42 pathway proteins in the cell membrane are involved in the cell podia formation in keratinocytes at NP125. NPWT may facilitate cell migration to accelerate wound healing.