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1.
J Am Chem Soc ; 145(42): 23143-23151, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37844138

RESUMO

High-mobility group box 1 (HMGB1) is a multifunctional protein. Upon injury or infection, HMGB1 is passively released from necrotic and activated dendritic cells and macrophages, where it functions as a cytokine, acting as a ligand for RAGE, a major receptor of innate immunity stimulating inflammation responses including the pathogenesis of cerebral ischemia/reperfusion (I/R) injury. Blocking the HMGB1/RAGE axis offers a therapeutic approach to treating these inflammatory conditions. Here, we describe a synthetic antibody (SA), a copolymer nanoparticle (NP) that binds HMGB1. A lightly cross-linked N-isopropylacrylamide (NIPAm) hydrogel copolymer with nanomolar affinity for HMGB1 was selected from a small library containing trisulfated 3,4,6S-GlcNAc and hydrophobic N-tert-butylacrylamide (TBAm) monomers. Competition binding experiments with heparin established that the dominant interaction between SA and HMGB1 occurs at the heparin-binding domain. In vitro studies established that anti-HMGB1-SA inhibits HMGB1-dependent ICAM-1 expression and ERK phosphorylation of HUVECs, confirming that SA binding to HMGB1 inhibits the proteins' interaction with the RAGE receptor. Using temporary middle cerebral artery occlusion (t-MCAO) model rats, anti-HMGB1-SA was found to accumulate in the ischemic brain by crossing the blood-brain barrier. Significantly, administration of anti-HMGB1-SA to t-MCAO rats dramatically reduced brain damage caused by cerebral ischemia/reperfusion. These results establish that a statistical copolymer, selected from a small library of candidates synthesized using an "informed" selection of functional monomers, can yield a functional synthetic antibody. The knowledge gained from these experiments can facilitate the discovery, design, and development of a new category of drug.


Assuntos
Isquemia Encefálica , Proteína HMGB1 , Traumatismo por Reperfusão , Ratos , Animais , Proteína HMGB1/metabolismo , Encéfalo/metabolismo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Inflamação/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Heparina/metabolismo
2.
Nutrients ; 14(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35334892

RESUMO

Sex steroids modify feeding behavior and body weight regulation, and androgen reportedly augments food intake and body weight gain. To elucidate the role of endogenous androgens in the feeding regulation induced by reduced glucose availability, we examined the effect of gonadectomy (orchiectomy) on food intake and orexin A neuron's activity in the lateral hypothalamic/perifornical area (LH/PFA) in response to reduced glucose availability (glucoprivation) induced by 2-deoxy-d-glucose (2DG) administration in male rats. Rats (7W) were bilaterally orchiectomized (ORX group) or sham operated (Sham group). Seventeen days after the surgery, food intake response to 2DG (400 mg/kg, i.v.) was measured for 4 h after the infusion. The same experiment was performed for the immunohistochemical examination of c-Fos-expressing orexin A neurons in the LH/PFA and c-Fos expression in the arcuate nucleus (Arc). Food intake induced by glucoprivation was greater in the ORX group than the Sham group, and the glucoprivation-induced food intake was inversely correlated with plasma testosterone concentration. Glucoprivation stimulated c-Fos expression of the orexin A neurons at the LH/PFA and c-Fos expression in the dorsomedial Arc. The number and percentage of c-Fos-expressing orexin A neurons in the LH/PFA and c-Fos expression in the dorsomedial Arc were significantly higher in the ORX group than the Sham group. This indicates that endogenous androgen, possibly testosterone, diminishes the food intake induced by reduced glucose availability, possibly via the attenuated activity of orexin A neuron in the LH/PFA and neurons in the dorsomedial Arc.


Assuntos
Androgênios , Neuropeptídeos , Androgênios/metabolismo , Androgênios/farmacologia , Animais , Ingestão de Alimentos/fisiologia , Glucose/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Orexinas/metabolismo , Ratos
3.
Nutrients ; 12(3)2020 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-32235766

RESUMO

Our previous study demonstrated that chronic estrogen replacement in ovariectomized rats reduces food intake and augments c-Fos expression in the suprachiasmatic nucleus (SCN), specifically during the light phase. Here, we hypothesized that serotonergic neurons in the central nervous system (CNS), which have anorectic action and play a role in regulating circadian rhythm, mediate the light phase-specific anorectic action of estrogen, and that selective serotonin reuptake inhibitors (SSRIs) mimic the hypophagic action of estrogen. Female Wistar rats were ovariectomized and treated with estradiol (E2) or cholesterol by subcutaneously implanting a silicon capsule containing E2 or cholesterol. Then, half of the cholesterol-treated rats were injected with the SSRI fluoxetine (5 mg/kg) (FLX group), while the remaining rats in the cholesterol-treated group (CON group) and all those in the E2 group were injected with saline subcutaneously twice daily at the onsets of the light and dark phases. Both E2 and FLX reduced food intake during the light phase but not the dark phase, and reduced body weight gain. In addition, both E2 and FLX augmented the c-Fos expression in the SCN, specifically during the light phase. These data indicate that FLX exerts estrogen-like antiobesity and hypophagic actions by modifying circadian feeding patterns, and suggest that estrogen regulates circadian feeding rhythm via serotonergic neurons in the CNS.


Assuntos
Depressores do Apetite , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Estrogênios/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Fluoxetina/farmacologia , Ovariectomia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Estrogênios/farmacologia , Feminino , Ratos , Ratos Wistar , Neurônios Serotoninérgicos/fisiologia , Serotonina/metabolismo , Aumento de Peso/efeitos dos fármacos
4.
Bioorg Med Chem ; 28(7): 115350, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32115336

RESUMO

A triplex-forming oligonucleotide (TFO) can recognize the homopurine-homopyrimidine sequence in DNA duplexes and inhibit the transcription of targeted mRNAs. Recently, we reported that N-acetyl-2,7-diamino-1,8-naphthyridine (DANac), incorporated into a TFO, has high binding ability and base recognition selectivity for the pyrimidine bases in the purine-rich chain of the DNA duplex at pH 7.4. However, it was found in this study that the difference in the Tm values between the pyrimidine bases and purine bases decreased by more than 4 °C at pH 6.0-7.0. To improve the low base recognition selectivity of the TFO, we designed a new artificial base, DAQac, with a quinoline skeleton. The Tm values of the triplexes containing DAQac:T-A or DAQac:C-G were more than 13 °C higher than those of the triplexes containing DAQac:A-T or DAQac:G-C at pH 7.4. We also observed that under more acidic conditions (pH 6.0-7.0), the base recognition selectivity of DAQac in a triplex was higher than that of DANac, although the binding ability of DAQac in a triplex was similar to that of DANac. Additionally, we found that DAQac, incorporated into the TFO, could accurately recognize the MeC-G base pair in the hairpin DNA, similar to the C-G base pair.


Assuntos
Pareamento de Bases , DNA/química , Oligonucleotídeos/química , Quinolinas/química , Animais , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Conformação de Ácido Nucleico
5.
Front Cell Neurosci ; 13: 312, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31417358

RESUMO

Here, we describe a cost-effective setup for targeted photoconversion of fluorescent signals into electron dense ones. This approach has offered invaluable insights in the morphology and function of fine neuronal structures. The technique relies on the localized oxidation of diaminobenzidine (DAB) mediated by excited fluorophores. This paper includes a detailed description of how to build a simple photoconversion setup that can increase reliability and throughput of this well-established technique. The system described here, is particularly well-suited for thick neuronal tissue, where light penetration and oxygen diffusion may be limiting DAB oxidation. To demonstrate the system, we use Correlative Light and Electron Microscopy (CLEM) to visualize functionally-labeled individual synaptic vesicles released onto an identified layer 5 neuron in an acute cortical slice. The setup significantly simplifies the photoconversion workflow, increasing the depth of photoillumination, improving the targeting of the region of interest and reducing the time required to process each individual sample. We have tested this setup extensively for the photoconversion of FM 1-43FX and Lucifer Yellow both excited at 473 nm. In principle, the system can be adapted to any dye or nanoparticle able to oxidize DAB when excited by a specific wavelength of light.

6.
Biochem Biophys Rep ; 18: 100638, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31032430

RESUMO

Excessive intake of fructose increases lipogenesis in the liver, leading to hepatic lipid accumulation and development of fatty liver disease. Metabolic alterations in the liver due to fructose intake have been reported in many studies, but the effect of fructose administration on hepatic gluconeogenesis is not fully understood. The aim of this study was to evaluate the acute effects of fructose administration on fasting-induced hepatic gluconeogenesis. C57BL/6J mice were administered fructose solution after 14 h of fasting and plasma insulin, glucose, free fatty acids, and ketone bodies were analysed. We also measured phosphorylated AKT and forkhead box O (FoxO) 1 protein levels and gene expression related to gluconeogenesis in the liver. Furthermore, we measured glucose production from pyruvate after fructose administration. Glucose-administered mice were used as controls. Fructose administration enhanced phosphorylation of AKT in the liver, without increase of blood insulin levels. Blood free fatty acids and ketone bodies concentrations were as high as those in the fasting group after fructose administration, suggesting that insulin-induced inhibition of lipolysis did not occur in mice administered with fructose. Fructose also enhanced phosphorylation of FoxO1 and suppressed gluconeogenic gene expression, glucose-6-phosphatase activity, and glucose production from pyruvate. The present study suggests that acute fructose administration suppresses fasting-induced hepatic gluconeogenesis in an insulin-independent manner.

7.
J Diabetes Investig ; 10(6): 1527-1536, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30868726

RESUMO

AIMS/INTRODUCTION: We compared the efficacy and safety of insulin degludec/aspart (IDegAsp) twice-daily injections with insulin glargine 300 U/mL and insulin glulisine basal-bolus therapy (Gla300/Glu) using insulin glargine 300 U/mL (Gla300) and insulin glulisine (Glu). MATERIALS AND METHODS: A total of 20 patients with type 2 diabetes mellitus were treated with IDegAsp twice-daily injections; achievement of target preprandial glucose concentration of 100-130 mg/dL at breakfast and supper was determined using a wearable flash glucose monitoring system. Patients were later switched to Gla300/Glu basal-bolus therapy before breakfast and before supper. Data were collected on days 2-4 and days 12-14 for each treatment period. The study's primary efficacy end-point was the mean percentage of time with a target glucose range of 70-180 mg/dL, and safety end-points were the mean percentage of time with hypoglycemia having glucose levels <70 mg/dL, clinically important hypoglycemia with glucose levels <54 mg/dL and nocturnal (00.00-06.00) hypoglycemia. RESULTS: Considering efficacy, the mean percentage of time for the target glucose range of IDegAsp was significantly lower than that of Gla300/Glu (73.1 [69.4-81.1] vs 84.2 [80.2-93.1], P = 0.001). Considering safety, the mean percentages of hypoglycemia (<70 mg/dL; 2.1 [0.0-9.4] vs 14.4 [4.4-22.3]), clinically important hypoglycemia (<54 mg/dL; 0.0 [0.0-0.2] vs 1.9 [0.0-5.6]) and nocturnal (00.00-06.00 hours) hypoglycemia (0.5 [0.0-5.9] vs 8.9 [3.1-11.8]) of Gla300/Glu were significantly lower than those of IDegAsp (P = 0.012, 0.036 and 0.007, respectively). CONCLUSIONS: When compared with the IDegAsp twice-daily injections, Gla300/Glu basal-bolus therapy might achieve more effective glycemic control without hypoglycemic risk.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemia/prevenção & controle , Hipoglicemiantes/uso terapêutico , Insulina Aspart/uso terapêutico , Insulina Glargina/uso terapêutico , Insulina de Ação Prolongada/uso terapêutico , Insulina/análogos & derivados , Idoso , Biomarcadores/análise , Glicemia/análise , Feminino , Seguimentos , Hemoglobinas Glicadas/análise , Humanos , Insulina/uso terapêutico , Masculino , Segurança do Paciente , Prognóstico
8.
J Control Release ; 295: 13-20, 2019 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-30578808

RESUMO

Protein affinity reagents (PARs), frequently antibodies, are essential tools for basic research, diagnostics, separations and for clinical applications. However, there is growing concern about the reproducibility, quality and cost of recombinant and animal-derived antibodies. This has prompted the development of alternatives that could offer economic, and time-saving advantages without the use of living organisms. Synthetic copolymer nanoparticles (NPs), engineered with affinity for specific protein targets, are potential alternatives to PARs. Although there are now a number of examples of abiotic protein affinity reagents (APARs), most have been evaluated in vitro limiting a realistic assessment of their potential for more demanding, practical in vivo applications. We demonstrate for the first time that an abiotic copolymer hydrogel nanoparticle (NP1) engineered to bind a key signaling protein, vascular endothelial growth factor (VEGF165), functions in vivo to suppress tumor growth by regulating angiogenesis. Lightly cross-linked N-isopropylacrylamide based NPs that incorporate both sulfated N-acetylglucosamine and hydrophobic monomers were optimized by dynamic chemical evolution for VEGF165 affinity. NP1 efficacy in vivo was evaluated by systemic administration to tumor-bearing mice. The study found that NP1 suppresses tumor growth and reduces tumor vasculature density. Combination therapy with doxorubicin resulted in increased doxorubicin concentration in the tumor and dramatic inhibition of tumor growth. NP1 treatment did not show off target anti-coagulant activity. In addition, >97% of injected NPs are rapidly excreted from the body following IV injection. These results establish the use of APARs as inhibitors of protein-protein interactions in vivo and may point the way to their broader use as abiotic, cost effective protein affinity reagents for the treatment of certain cancers and more broadly for regulating signal transduction.


Assuntos
Acrilamidas/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acrilamidas/administração & dosagem , Acrilamidas/química , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/química , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Humanos , Masculino , Camundongos Endogâmicos BALB C , Nanopartículas/administração & dosagem , Nanopartículas/química , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-29097993

RESUMO

Chronic estrogen replacement in ovariectomized rats attenuates food intake and enhances c-Fos expression in the suprachiasmatic nucleus (SCN), specifically during the light phase. S-equol, a metabolite of daidzein, has a strong affinity for estrogen receptor (ER)-ß and exerts estrogenic activity. The purpose of the present study was to elucidate whether S-equol exerts an estrogen-like anorectic effect by modifying the regulation of the circadian feeding rhythm in ovariectomized rats. Ovariectomized female Wistar rats were divided into an estradiol (E2)-replaced group and cholesterol (vehicle; Veh)-treated group. These animals were fed either a standard diet or an S-equol-containing diet for 13 days. Then, the brain, uterus, and pituitary gland were collected along with blood samples. In the rats fed the standard diet, E2 replacement attenuated food intake (P < 0.001) and enhanced c-Fos expression in the SCN (P < 0.01) during the light phase. Dietary S-equol supplementation reduced food intake (P < 0.01) and increased c-Fos expression in the SCN (P < 0.01) in the Veh-treated rats but not in the E2-replaced rats during the light phase. Dietary S-equol did not alter ER-α expression in the medial preoptic area or the arcuate nucleus, nor did dietary S-equol affect pituitary gland weight or endometrial epithelial layer thickness. By contrast, E2 replacement not only markedly decreased ER-α expression in these brain areas (P < 0.001) but also increased both the pituitary gland weight (P < 0.001) and the endometrial epithelial layer thickness (P < 0.001). Thus, dietary S-equol acts as an anorectic by modifying the diurnal feeding pattern in a manner similar to E2 in ovariectomized rats; however, the mechanism of action is not likely to be mediated by ER-α. The data suggest a possibility that dietary S-equol could be an alternative to hormone replacement therapy for the prevention of hyperphagia and obesity with a lower risk of adverse effects induced by ER-α stimulation.

10.
J Nutr Biochem ; 50: 83-94, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29040839

RESUMO

Phosphatidylcholines (PCs), a major class of human plasma phospholipids, are composed of highly diverse fatty acids. Because the dietary carbohydrate-fat ratio alters the hepatic fatty acid metabolism, plasma fatty acids that bind PCs, which are secreted as lipoproteins from the liver, may be affected by long-term consumption of a high-carbohydrate diet or a high-fat diet. Therefore, in this study, we profiled the plasma PC species comprehensively in formulated dieting conditions to identify those phospholipid molecules that reflect the dietary carbohydrate-fat ratio. C57BL6J mice were fed diets containing different amounts of fat for 8 weeks, and plasma PC species were analyzed under fasting conditions using liquid chromatography-mass spectrometry. In addition, a cross-sectional study of 78 middle-aged Japanese men, who participated in health checkups, was conducted. Nutrient intakes were estimated by a brief self-administered diet-history questionnaire. The plasma PC profiles changed depending on the dietary carbohydrate-fat ratio. Especially, PC (16:0/16:1) and PC (16:0/18:1) levels increased as the dietary carbohydrate-fat ratio increased in human and mouse, suggesting that these PC species reflected the increase in de novo lipogenesis and might become useful biomarkers of the dietary carbohydrate-fat ratio. Since these PCs act as ligands for peroxisome proliferator-activated receptor α, PC species reflecting the dietary carbohydrate-fat ratio may influence metabolism of glucose and lipids.


Assuntos
Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Ácidos Graxos/sangue , Fosfatidilcolinas/sangue , Algoritmos , Animais , Biomarcadores/sangue , Estudos Transversais , Dieta , Ácidos Graxos/análise , Genes Reporter , Células HEK293 , Humanos , Japão , Masculino , Programas de Rastreamento , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fosfatidilcolinas/química , Análise de Componente Principal , Proteínas Recombinantes/metabolismo , Autorrelato
11.
Nat Chem ; 9(7): 715-722, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28644480

RESUMO

Protein affinity reagents are widely used in basic research, diagnostics and separations and for clinical applications, the most common of which are antibodies. However, they often suffer from high cost, and difficulties in their development, production and storage. Here we show that a synthetic polymer nanoparticle (NP) can be engineered to have many of the functions of a protein affinity reagent. Polymer NPs with nM affinity to a key vascular endothelial growth factor (VEGF165) inhibit binding of the signalling protein to its receptor VEGFR-2, preventing receptor phosphorylation and downstream VEGF165-dependent endothelial cell migration and invasion into the extracellular matrix. In addition, the NPs inhibit VEGF-mediated new blood vessel formation in Matrigel plugs in vivo. Importantly, the non-toxic NPs were not found to exhibit off-target activity. These results support the assertion that synthetic polymers offer a new paradigm in the search for abiotic protein affinity reagents by providing many of the functions of their protein counterparts.


Assuntos
Nanopartículas/química , Polímeros/química , Engenharia de Proteínas , Fator A de Crescimento do Endotélio Vascular/química , Proliferação de Células , Relação Dose-Resposta a Droga , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Vet J ; 202(3): 455-61, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25312719

RESUMO

Feline nasal tumours (NTs) are locally invasive and occasionally metastasise to distant sites. Although palliative hypofractionated radiotherapy (HRT) is used, its efficacy and long-term complications have not been adequately evaluated. The purpose of this study was to evaluate the efficacy of HRT in treating feline malignant NTs, including monitoring improvement in clinical signs, acute and late complications, and prognosis. The medical records of 65 cats with malignant NTs treated with HRT were included. Overall survival (OS) and progression-free survival (PFS) were calculated using the Kaplan-Meier method. The log-rank test and Cox proportional hazard model were used to evaluate factors that influenced OS and PFS. Clinical signs improved in 86.2% of cats following radiotherapy. Acute complications were observed in 58.5% of cats but were manageable and acceptable. Among late complications, cataract was most frequently observed (20.5%), and atrophy of the entire eyeball and osteochondroma at the irradiation site were each observed in two cats. The median OS and PFS in 65 cats were 432 days and 229 days, respectively. No significant difference between OS of cats with nasal lymphoma and that of cats with other tumours was observed. Despite some limitations due to the retrospective nature of the study, palliative HRT for feline NTs can be considered a useful treatment option because of the high incidence of improvement and more favourable prognosis, although it may be preferable not to use the hypofractionated regimen in young cats with lymphoma that are expected to survive for a long period.


Assuntos
Doenças do Gato/radioterapia , Neoplasias Nasais/veterinária , Radioterapia/veterinária , Animais , Doenças do Gato/mortalidade , Gatos , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Relação Dose-Resposta à Radiação , Feminino , Estimativa de Kaplan-Meier , Masculino , Neoplasias Nasais/mortalidade , Neoplasias Nasais/radioterapia , Modelos de Riscos Proporcionais , Radioterapia/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
13.
J Physiol Sci ; 64(3): 203-11, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24676683

RESUMO

In order to elucidate the involvement of melanin-concentrating hormone (MCH) and orexin-A (ORX-A) neurons of the perifornical/lateral hypothalamic areas (PF/LH) in the regulation of food intake induced by acutely reduced glucose availability, we examined the food intake response and c-Fos expression in the MCH and ORX-A neurons in the PF/LH during 2-deoxy-D-glucose (2DG)-induced glucoprivation (400 mg/kg; i.v.) and systemic insulin-induced hypoglycemia (5 U/kg; s.c.) in male Wistar rats. The administration of both 2DG and insulin stimulated food intake and induced c-Fos expression in the ORX-A neurons corresponding to food intake, but not in the MCH neurons. These data indicate that ORX-A neurons, but not MCH neurons, play a role in the short-term regulation of food intake, and that the input signals for the neurons containing MCH and ORX-A are different, and these neurons play different roles in the regulation of feeding behavior.


Assuntos
Ingestão de Alimentos , Comportamento Alimentar , Hiperglicemia/metabolismo , Hormônios Hipotalâmicos/metabolismo , Hipotálamo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Melaninas/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Hormônios Hipofisários/metabolismo , Animais , Glicemia/metabolismo , Regulação da Temperatura Corporal , Desoxiglucose/administração & dosagem , Modelos Animais de Doenças , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético , Comportamento Alimentar/efeitos dos fármacos , Hiperglicemia/induzido quimicamente , Hiperglicemia/psicologia , Hipotálamo/efeitos dos fármacos , Insulina , Masculino , Neurônios/efeitos dos fármacos , Orexinas , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos Wistar , Fatores de Tempo
14.
Bioorg Med Chem Lett ; 23(23): 6390-5, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24125881

RESUMO

The glycopolymers for glycosaminoglycan mimic were synthesized, and the inhibitory effects of Alzheimer's ß-secretase (BACE-1) were examined. The regio-selective sulfation was conducted on N-acetyl glucosamine (GlcNAc), and the acrylamide derivatives were synthesized with the consequent sulfated GlcNAc. The glycopolymers were synthesized with acrylamide using radical initiator. The glycopolymer with sulfated GlcNAc showed the strong inhibitory effect on BACE-1, and the inhibitory effects were dependent on the sulfation positions. Especially, glycopolymers carrying 3,4,6-O-sulfo-GlcNAc showed the strong inhibitory effect. The docking simulation suggested that glycopolymers bind to the active site of BACE-1.


Assuntos
Acetilglucosamina/análogos & derivados , Acetilglucosamina/farmacologia , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Glicosaminoglicanos/síntese química , Glicosaminoglicanos/farmacologia , Sulfatos/síntese química , Acetilglucosamina/síntese química , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Glicosaminoglicanos/química , Humanos , Sulfatos/química
15.
J Pharm Biomed Anal ; 83: 293-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23777617

RESUMO

A combination of methods is required to achieve separation of intact proteins and subsequently perform structure analysis to examine their unstable or external structures. The aim of this study was to develop a method of structure analysis in intact proteins after purification. Transferrin from human plasma was trapped by membrane-immobilized anti-transferrin antibody, which was produced by non-denaturing two-dimensional electrophoresis (2-DE), and transferred to a polyvinylidene fluoride (PVDF) membrane and stained with Ponceau S. The antigen transferrin was eluted by rinsing the membrane with trifluoroacetic acid (TFA) or aspartic acid. In addition, a method was established by which the purified human transferrin was enzymatically digested on a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) target plate. Thus, after purification of the human transferrin antigen from tens of microlitres of human plasma using an immunoaffinity membrane, transferrin polypeptide fragments were obtained on the plate following digestion with pepsin in the presence of 0.1% TFA or endoproteinase Lys-C or Lys-C/trypsin with 0.001% sodium dodecyl sulphate (SDS). The results indicated that the combined methods of isolation using an immunoaffinity membrane and enzymatic digestion on a MALDI-TOF MS plate could be applied to the purification and microanalysis of antigens. This approach would be particularly applicable to the analysis of the primary structure and the less stable and highly accessible regions of antigens from limited sample volumes.


Assuntos
Antígenos/química , Antígenos/imunologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Anticorpos/imunologia , Ácido Aspártico/química , Eletroforese em Gel Bidimensional/métodos , Humanos , Peptídeos/química , Peptídeos/imunologia , Polivinil/química , Transferrina/imunologia , Ácido Trifluoracético/química
16.
Oncol Lett ; 3(2): 321-324, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22740904

RESUMO

Protein kinase AKT mediates cell proliferation and survival signals, and also contributes to cancer progression. Increased expression and/or activation of AKT is involved in a variety of human cancers. In cells treated with sage or rosemary extract, mRNA and protein expression levels of AKT1 were reduced compared with those of the control cells 48 h after the herbal treatments. We found that terpinolene, a common component of sage and rosemary, markedly reduced the protein expression of AKT1 in K562 cells and inhibited cell proliferation.

17.
Adv Hematol ; 2012: 843085, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22505939

RESUMO

PI3K/AKT/PTEN pathway is important in the regulation of angiogenesis mediated by vascular endothelial growth factor in many tumors including leukemia. The signaling pathway is activated in leukemia patients as well as leukemia cell lines together with a decrease in the expression of PTEN gene. The mechanism by which the signaling pathway regulates angiogenesis remains to be further elucidated. However, it has become an attractive target for drug therapy against leukemia, because angiogenesis is a key process in malignant cell growth. In this paper, we will focus on the roles and mechanisms of PI3K/AKT/PTEN pathway in regulating angiogenesis.

18.
Lung Cancer Int ; 2012: 659365, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-26316936

RESUMO

Tobacco smoke and radioactive radon gas impose a high risk for lung cancer. The radon-derived ionizing radiation and some components of cigarette smoke induce oxidative stress by generating reactive oxygen species (ROS). Respiratory lung cells are subject to the ROS that causes DNA breaks, which subsequently bring about DNA mutagenesis and are intimately linked with carcinogenesis. The damaged cells by oxidative stress are often destroyed through the active apoptotic pathway. However, the ROS also perform critical signaling functions in stress responses, cell survival, and cell proliferation. Some molecules enhance radiation-induced tumor cell killing via the reduction in DNA repair levels. Hence the DNA repair levels may be a novel therapeutic modality in overcoming drug resistance in lung cancer. Either survival or apoptosis, which is determined by the balance between DNA damage and DNA repair levels, may lender the major problems in cancer therapy. The purpose of this paper is to take a closer look at risk factor and at therapy modulation factor in lung cancer relevant to the ROS.

19.
Mol Med Rep ; 5(2): 567-9, 2012 02.
Artigo em Inglês | MEDLINE | ID: mdl-22075938

RESUMO

Cip-interacting zinc finger protein 1 (Ciz1) stimulates DNA replication and has been implicated in the tumorigenesis of breast cancer cells. In order to investigate the possibility of using medicinal glucocorticoids against breast cancer, we studied whether certain glucocorticoids affect the expression of Ciz1. The in vitro effect of clobetasol treatment on the reduction of Ciz1 expression was detected by reverse transcriptase-polymerase chain reaction. Western blotting also confirmed the down-regulation of the protein in a dose-dependent manner upon clobetasol treatment in U937 monocytoid cells. Furthermore, we found that Ciz1 protein expression was decreased after pre-treatment of the cells with clobetasol and genistein. An extract of Lens culinaris also had a synergistic effect on the repression of Ciz1 protein expression.


Assuntos
Anti-Inflamatórios/farmacologia , Anticarcinógenos/farmacologia , Clobetasol/farmacologia , Regulação para Baixo/efeitos dos fármacos , Genisteína/farmacologia , Proteínas Nucleares/metabolismo , Replicação do DNA , Sinergismo Farmacológico , Humanos , Lens (Planta)/química , Proteínas Nucleares/genética , Células U937
20.
Int J Mol Med ; 29(2): 324-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22076618

RESUMO

In order to investigate how glucocorticoids affect the expression of secretory leukocyte peptidase inhibitor (SLPI), which is overexpressed in a variety of cancers, clobetasol was added to cell culture medium of U937 cells and the SLPI mRNA levels were examined. The in vitro effect of the treatment on SLPI expression was detected by reverse transcriptase-polymerase chain reaction. Clobetasol treatment of U937 cells induced an up- and down-regulation of SLPI expression in a dose-dependent manner. Western blotting confirmed the down-regulation of SLPI protein expression. We hypothesized a loop formation in the SLPI genome domain, in which the glucocorticoid receptor regulates bi-directional transcriptional activity.


Assuntos
Clobetasol/farmacologia , Glucocorticoides/farmacologia , Inibidor Secretado de Peptidases Leucocitárias/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Modelos Biológicos , Inibidor Secretado de Peptidases Leucocitárias/metabolismo , Células U937
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