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1.
Zhonghua Yi Xue Za Zhi ; 99(24): 1887-1892, 2019 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-31269585

RESUMO

Objective: To clarify the effect of FOXR2 on the proliferation and apoptosis of prostate cancer cells and to reveal the mechanism. Methods: The expression of FOXR2 in clinical samples of prostate cancer were detected by Quantitative Real-time PCR (qRT-PCR) and Western blotting. The CCK8 proliferation kit and the Annexin V-FITC apoptosis kit, flow cytometry were used to detect the proliferation and apoptosis of prostate cancer cells with or without the FOXR2 knockdown. Combined with the results of microRNA chip, we predicted the related miR-152 and detected the relationship between miR-152 and FOXR2 by luciferase reporter gene assay. The correlation between HOTAIR and miR-152 is clearly defined by software prediction and qRT-PCR. Results: FOXR2 had a relatively high expression in the prostate cancer tissue.The mRNA expression of FOXR2 is 4.9 times that of adjacent tissues, and the protein level was also significantly up-regulated. In the PC3 cell line, the specific knock-down of FOXR2 inhibits the proliferation of cells and promotes cell apoptosis. According to the microRNA chip results and luciferase reporter gene assay, we found miR-152 could regulate the expression of FOXR2; and FOXR2 3 'UTR had two miR-152 binding sites, all of which could control the expression of FOXR2. The results of LNCediting and qRT-PCR suggest that HOTAIR is negatively correlated with the expression of miR-152, and is involved in the regulation of miR-152 expression in prostate cancer. Conclusion: FOXR2 up-regulation can promote the proliferation and inhibit the apoptosis of prostate cancer cells because that HOTAIR restrains the expression of miR-152.


Assuntos
Fatores de Transcrição Forkhead/genética , MicroRNAs/genética , Neoplasias da Próstata , RNA Longo não Codificante/genética , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino
2.
Clin Exp Immunol ; 177(1): 341-52, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24634990

RESUMO

Chronic obstructive pulmonary disease (COPD) is characterized by an abnormal regulatory T cell (T(reg)) response and increases in T helper type 1 (Th1) and Th17 cell responses. It is unclear if dysregulation of microRNAs (miRNA) within T(reg) cells contributes to the abnormal inflammatory response in COPD. In this study, we aimed to compare the miRNA profile of COPD T(reg) cells with that of healthy controls and to explore the function of differentially expressed miRNAs. We first obtained T(reg) and T effector cells (Teff ) from peripheral blood of non-smokers, unaffected current smokers and COPD current smokers. Then, we assessed their miRNA expression by microarray analysis followed by real-time reverse transcription-polymerase chain reaction (RT-PCR) validation of particular miRNAs. Six and 96 miRNAs were expressed differentially in COPD T(reg) cells versus T(reg) cells of healthy non-smokers and healthy smokers, whereas no differences were found in miRNA expression in T(eff) cells. We found that miR-199a-5p was repressed by approximately fourfold in T(reg) cells of COPD patients compared to healthy smokers (P < 0·05). In addition, miR-199a-5p was over-expressed in T(reg) cells compared to Teff cells (P < 0·001) and had significant over-representation of its target genes in the T(reg) transcriptome, being associated with the transforming growth factor (TGF)-ß activation pathway (P < 0·01). We also confirmed the function of miR-199a5p in an in-vitro loss-of-function cell model running TaqMan® arrays of the human TGF-ß pathway. These findings suggest that the abnormal repression of miR-199a-5p in patients with COPD compared to unaffected smokers may be involved in modulating the adaptive immune balance in favour of a Th1 and Th17 response.


Assuntos
MicroRNAs/metabolismo , Doença Pulmonar Obstrutiva Crônica/imunologia , Fumar/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Adulto , Células Cultivadas , Doença Crônica , Regulação para Baixo , Feminino , Humanos , Masculino , MicroRNAs/genética , Análise em Microsséries , Pessoa de Meia-Idade , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
3.
Eur Rev Med Pharmacol Sci ; 24(14): 7550, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32744655

RESUMO

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Inhibition of miR-221 influences bladder cancer cell proliferation and apoptosis, by H. Liu, J.-K. Chang, J.-Q. Hou, Z.-H. Zhao, L.-D. Zhang, published in Eur Rev Med Pharmacol Sci 2017; 21 (14): 3193-3199-PMID: 28770966" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/13140.

4.
Neuroscience ; 159(2): 492-500, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19373968

RESUMO

With the use of a rabbit polyclonal antiserum against a conserved region (54-118) of C-peptide of human preproinsulin-like peptide 7, referred to herein as C-INSL7, neurons expressing C-INSL7-immunoreactivity (irC-INSL7) were detected in the pontine nucleus incertus, the lateral or ventrolateral periaqueductal gray, dorsal raphe nuclei and dorsal substantia nigra. Immunoreactive fibers were present in numerous forebrain areas, with a high density in the septum, hypothalamus and thalamus. Pre-absorption of C-INSL7 antiserum with the peptide C-INSL7 (1 microg/ml), but not the insulin-like peptide 7 (INSL7; 1 microg/ml), also known as relaxin 3, abolished the immunoreactivity. Optical imaging with a voltage-sensitive dye bis-[1,3-dibutylbarbituric acid] trimethineoxonol (DiSBAC4(3)) showed that C-INSL7 (100 nM) depolarized or hyperpolarized a small population of cultured rat hypothalamic neurons studied. Ratiometric imaging studies with calcium-sensitive dye fura-2 showed that C-INSL7 (10-1000 nM) produced a dose-dependent increase in cytosolic calcium concentrations [Ca2+]i in cultured hypothalamic neurons with two distinct patterns: (1) a sustained elevation lasting for minutes; and (2) a fast, transitory rise followed by oscillations. In a Ca2+-free Hanks' solution, C-INSL7 again elicited two types of calcium transients: (1) a fast, transitory increase not followed by a plateau phase, and (2) a transitory rise followed by oscillations. INSL7 (100 nM) elicited a depolarization or hyperpolarization in a small population of hypothalamic neurons, and an increase of [Ca2+]i with two patterns that were dissimilar from that of C-INSL7. [125I]C-INSL7 bindings to rat brain membranes were inhibited by C-INSL7 in a dose-dependent manner; the Kd and Bmax. values were 17.7 +/- 8.2 nM and 45.4 +/- 20.5 fmol/mg protein. INSL7 did not inhibit [125I]C-INSL7 binding to rat brain membranes, indicating that C-INSL7 and INSL7 bind to distinct binding sites. Collectively, our result raises the possibility that C-INSL7 acts as a signaling molecule independent from INSL7 in the rat CNS.


Assuntos
Encéfalo/metabolismo , Peptídeo C/metabolismo , Animais , Encéfalo/anatomia & histologia , Peptídeo C/farmacologia , Cálcio/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Eletrofisiologia/métodos , Fura-2/metabolismo , Hipotálamo/citologia , Isótopos de Iodo/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley , Tiobarbitúricos/metabolismo
5.
Eur J Clin Invest ; 39(4): 296-303, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19292885

RESUMO

BACKGROUND: Previous reports have indicated that statins could prevent bone loss in ovariectomized (OVX) rats and increase the expressions of osteogenic genes in cultured osteoblasts. In this study, we hypothesized that simvastatin might increase osteoblast number and protein expressions of osteogenic markers localized in bones in concomitance with the prevention of bone loss in OVX rats. MATERIALS AND METHODS: Fifty-four 3-month-old OVX and sham-operated (SHAM) female Sprague-Dawley rats were used. Simvastatin (10-20 mg kg(-1) day(-1)) was administrated orally for 6 weeks. Trabecular volume, osteoblast number and osteogenic proteins including BMP2, collagen type I and osteocalcin on bone sections obtained from lumbar vertebral body, distal femur and proximal tibia were measured. RESULTS: The results showed that SHAM rats had significantly less trabecular bone volume and osteoblast number than that of OVX rats 6 weeks after operation. Oral simvastatin treatment (10-20 mg kg(-1) day(-1)) increased bone volume and osteoblast number in the distal femurs, proximal tibiae and vertebrae of OVX rats. Furthermore, the osteoblastic cells with immuno-stained BMP2, collagen type I and osteocalcin in vertebral bones were significantly increased by simvastatin treatment (20 mg kg(-1) day(-1)) in OVX rats. CONCLUSIONS: This study demonstrates that simvastatin enhances the production of osteogenic proteins in bone and this effect may contribute to the prevention of bone loss in OVX rats.


Assuntos
Densidade Óssea/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Sinvastatina/farmacologia , Análise de Variância , Animais , Modelos Animais de Doenças , Feminino , Ovariectomia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
6.
Science ; 194(4262): 330-2, 1976 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-968485

RESUMO

[D-Ala2]-Met-enkephalinamide (DALA), a synthetic enkephalin analog designed by in vitro analysis, binds to opiate receptors almost as tightly as methionine-enkephalin. Since it is not susceptible to degradation by brain enzymes, low doses (5 to 10 micrograms) cause profound, long-lasting, morphine-like analgesia when microinjected into rat brain.


Assuntos
Analgesia , Oligopeptídeos/farmacologia , Animais , Cinética , Ligantes , Oligopeptídeos/metabolismo , Peptídeo Hidrolases/metabolismo , Ratos , Receptores de Droga , Relação Estrutura-Atividade
7.
Science ; 212(4490): 75-7, 1981 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-6259732

RESUMO

The synthetic peptide NH2-Tyr-Pro-Phe-Pro-CONH2 (morphiceptin), which is the amide of a fragment of the milk protein beta-casein, has morphinelike activities and is highly specific for morphine (mu) receptors but not for enkephalin (delta) receptors. It is as active as morphine in the guinea pig ileum but much less active in the mouse and rat vas deferens. The discovery of this specific morphine receptor ligand substantiates the hypothesis of multiple opiate receptors. The ligand, which may be of physiological significance since a very similar, or identical, activity can be detected in enzymatic digests of beta-casein, may prove useful for further investigation of the functions of opiate receptor subtypes.


Assuntos
Endorfinas/farmacologia , Receptores Opioides/efeitos dos fármacos , Animais , Ligação Competitiva , Caseínas/farmacologia , Di-Hidromorfina/metabolismo , Encefalinas/metabolismo , Guanosina Trifosfato/farmacologia , Cobaias , Íleo/efeitos dos fármacos , Masculino , Camundongos , Naloxona/metabolismo , Ratos , Sódio/farmacologia , Ducto Deferente/efeitos dos fármacos
8.
Science ; 219(4581): 189-91, 1983 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-6129700

RESUMO

Immunoreactive corticotropin-releasing factor (CRF) and dynorphin-(I-8) were visualized in rat hypothalamus by immunohistofluorescence with specific antibodies. In brains from colchicine-treated, adrenalectomized rats, neuronal perikarya with immunoreactive CRF were observed in the paraventricular nucleus of the hypothalamus. The CRF occurred together with the dynorphin-(1-8). However, the CRF immunoreactivity occurred only in a subpopulation of the dynorphin-(1-8) immunoreactive cells. These findings suggest that there may be a functional interrelationship of CRF with dynorphin-related opioid peptides and provide further evidence that neurons may contain more than one bioactive substance.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Endorfinas/metabolismo , Hipotálamo/metabolismo , Animais , Hormônio Liberador da Corticotropina/imunologia , Dinorfinas , Endorfinas/imunologia , Imunofluorescência , Hipotálamo/citologia , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Fragmentos de Peptídeos/metabolismo , Ratos
9.
Neuroscience ; 151(3): 701-10, 2008 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-18164555

RESUMO

Human immunodeficiency virus 1 (HIV-1) Tat protein is one of the neurotoxins involved in the pathogenesis of HIV-1-associated neuronal disorders. Combined electrophysiological and optical imaging experiments were undertaken to investigate whether HIV-1 Tat30-86, herein referred to as Tat30-86, acted directly or indirectly via the release of glutamate or both and to test its effect on the properties of spontaneous quantal events in cultured cortical neurons. Whole-cell patch recordings were made from cultured rat cortical neurons in either current- or voltage-clamp mode. Tat30-86 (50-1000 nM) induced in a population of cortical neurons a long-lasting depolarization, which was accompanied by a decrease of membrane resistance and persisted in a Krebs solution containing tetrodotoxin (TTX, 0.5 microM). Depolarizations were slightly reduced by pretreatment with glutamate receptor antagonists 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) (10 microM) and d-2-amino-5-phosphonovaleric acid (AP-5) (50 microM), and were markedly reduced in a Ca(2+)-free Krebs solution; the differences were statistically significant. Tat30-86-induced inward currents had a reversal potential between -30 and 0 mV. While not causing a noticeable depolarization, lower concentrations of Tat30-86 (10 nM) increased membrane excitability, as indicated by increased numbers of neuronal discharge in response to a step depolarizing pulse. Tat30-86 (10 nM) increased the frequency of spontaneous miniature excitatory postsynaptic currents (mEPSCs), while not significantly affecting their amplitude. Tat30-86 (10 nM) moderately increased the frequency as well as the amplitude of spontaneous miniature inhibitory postsynaptic currents (mIPSCs). Ratiometric Ca(2+) imaging studies showed that Tat30-86 produced three types of Ca(2+) responses: 1) a fast and transitory increase, 2) Ca(2+) oscillations, and 3) a fast increase followed by a plateau; the glutamate receptor antagonists eliminated the late component of Ca(2+) response. The result suggests that Tat30-86 is an active fragment and that it excites cortical neurons directly and indirectly via releasing glutamate from adjacent neurons.


Assuntos
Córtex Cerebral/citologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Bicuculina/farmacologia , Cálcio/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Estimulação Elétrica , Antagonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas GABAérgicos/farmacologia , Humanos , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp/métodos , Ratos , Ratos Sprague-Dawley , Tiobarbitúricos/metabolismo
10.
J Dent Res ; 97(8): 909-916, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29512401

RESUMO

Head and neck cancer (HNC)-derived cell lines represent fundamental models for studying the biological mechanisms underlying cancer development and precision therapies. However, mining the genomic information of HNC cells from available databases requires knowledge on bioinformatics and computational skill sets. Here, we developed a user-friendly web resource for exploring, visualizing, and analyzing genomics information of commonly used HNC cell lines. We populated the current version of GENIPAC with 44 HNC cell lines from 3 studies: ORL Series, OPC-22, and H Series. Specifically, the mRNA expressions for all the 3 studies were derived with RNA-seq. The copy number alterations analysis of ORL Series was performed on the Genome Wide Human Cytoscan HD array, while copy number alterations for OPC-22 were derived from whole exome sequencing. Mutations from ORL Series and H Series were derived from RNA-seq information, while OPC-22 was based on whole exome sequencing. All genomic information was preprocessed with customized scripts and underwent data validation and correction through data set validator tools provided by cBioPortal. The clinical and genomic information of 44 HNC cell lines are easily assessable in GENIPAC. The functional utility of GENIPAC was demonstrated with some of the genomic alterations that are commonly reported in HNC, such as TP53, EGFR, CCND1, and PIK3CA. We showed that these genomic alterations as reported in The Cancer Genome Atlas database were recapitulated in the HNC cell lines in GENIPAC. Importantly, genomic alterations within pathways could be simultaneously visualized. We developed GENIPAC to create access to genomic information on HNC cell lines. This cancer omics initiative will help the research community to accelerate better understanding of HNC and the development of new precision therapeutic options for HNC treatment. GENIPAC is freely available at http://genipac.cancerresearch.my/ .


Assuntos
Linhagem Celular Tumoral , Bases de Dados Genéticas , Genômica/métodos , Neoplasias de Cabeça e Pescoço/genética , Internet , Variações do Número de Cópias de DNA , Perfilação da Expressão Gênica , Genoma Humano , Humanos , Mutação , RNA Mensageiro/análise , Sequenciamento do Exoma
11.
Eur Rev Med Pharmacol Sci ; 21(14): 3193-3199, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28770966

RESUMO

OBJECTIVE: Janus kinase (JAK) - signal transducer and activator of transcription (STAT) signaling pathway participate in cell proliferation and apoptosis. Suppressors of cytokine signaling 3 (SOCS3) are negative regulators of JAK-STAT3. SOCS3 was found significantly declined, while microRNA-221 (miR-221) obviously up-regulated in bladder cancer tissue. Bioinformatics analysis revealed the complementary binding site between miR-221 and 3'-UTR of SOCS3. This study investigated the role of miR-221 in regulating SOCS3/JAK-STAT3 signaling pathway and bladder cancer cell proliferation and apoptosis. PATIENTS AND METHODS: Bladder cancer tumor tissue and para-carcinoma tissue were collected from patients to test miR-221 and SOCS3 expressions. Dual luciferase assay was used to test the targeting regulatory effect of miR-221 on SOCS3. MiR-221, SOCS3, p-JAK1, p-JAK2, and survivin expressions were compared in T24 and HBEC cells. T24 cells were divided into miR-NC, miR-221 inhibitor, pSicoR-blank, pSicoR-SOCS3, and miR-221 inhibitor + pSicoR-SOCS3 groups. Flow cytometry was applied to detect cell apoptosis. EdU staining was adopted to evaluate cell proliferation. RESULTS: MiR-221 significantly increased, while SOCS3 obviously reduced in bladder cancer tissue compared with para-carcinoma tissue. MiR-221 targeted inhibited SOCS3 expression. MiR-221, phosphorylated JAK1 (p-JAK1), phosphorylated JAK2 (p-JAK2), phosphorylated STAT3 (p-STAT3), and survivin levels markedly up-regulated, whereas SOCS3 expression apparently declined in T24 cells compared with that in HBEC cells. MiR-221 inhibitor and/or pSicoR-SOCS3 elevated SOCS3 expression, decreased p-JAK1, p-JAK2, p-STAT3, and survivin levels, enhanced cell apoptosis, and attenuated cell proliferation. CONCLUSIONS: MiR-221 elevated, while SOCS3 reduced in bladder cancer tissue. Inhibition of miR-221 suppressed T24 cell proliferation and induced apoptosis by up-regulating SOCS3 expression, lowering JAK-STAT3 signaling pathway activity, and attenuating survivin expression.


Assuntos
Apoptose , Proliferação de Células , MicroRNAs/metabolismo , Neoplasias da Bexiga Urinária/patologia , Regiões 3' não Traduzidas , Idoso , Antagomirs/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Feminino , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Janus Quinase 1/metabolismo , Janus Quinase 2/metabolismo , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Fosforilação , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Alinhamento de Sequência , Transdução de Sinais/efeitos dos fármacos , Survivina , Regulação para Cima , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
12.
Oncogene ; 14(18): 2127-36, 1997 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-9174048

RESUMO

We have previously shown that p53 disruption sensitizes certain cancer cell types to cisplatin (CDDP) (Fan et al., 1995). In the present study we investigated the role of the p53 downstream effector, p21CIP1/WAF1 (p21), in this sensitization. Studies were performed in human colon cancer HCT-116 cells and murine embryonic fibroblasts (MEF) with intact versus disrupted p21 genes. For comparison, HCT-116 cells lacking p53 function were also prepared through stable transfection with the human papillomavirus type-16 E6 gene. HCT-116/E6 cells were found to be more sensitive than control transfectants to CDDP and another DNA crosslinking agent, nitrogen mustard (HN2). HCT-116 cells with disrupted p21 genes also exhibited greater CDDP and HN2-sensitivity than parental HCT-116 cells. In contrast, the clonogenic survival of HCT-116 cells exposed to ionizing radiation, adriamycin, taxol or vincristine was not affected by p53 or p21 disruption. Sensitization of HCT-116/p21-/- cells to CDDP and HN2 was not limited to the HCT-116 cell background since MEF from p21 knockout mice were also more sensitive to these DNA crosslinking agents. Investigations into a possible cause of this enhanced sensitivity revealed that HCT-116 cells lacking p53 or p21 function exhibited a reduced ability to repair cisplatin-damaged CAT-reporter plasmids transfected into the cells. In addition, we found that HCT-116/p21-/- cells were much more susceptible to HN2-induced cell cycle delay than parental cells. Our results suggest that p21 disruption preferentially sensitizes at least some cell types to DNA crosslinking agents.


Assuntos
Cisplatino/farmacologia , Ciclinas/genética , Genes p53 , Mecloretamina/farmacologia , Proteínas Repressoras , Animais , Antineoplásicos/farmacologia , Antineoplásicos Alquilantes/farmacologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Cloranfenicol O-Acetiltransferase/efeitos dos fármacos , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/efeitos dos fármacos , Ciclinas/metabolismo , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fase G2/efeitos dos fármacos , Fase G2/genética , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Camundongos , Camundongos Transgênicos , Proteínas Oncogênicas Virais/genética , Plasmídeos/genética , Radiossensibilizantes/farmacologia , Fase S/efeitos dos fármacos , Fase S/genética , Transfecção
13.
Diabetes ; 39(6): 752-6, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2189768

RESUMO

Recent interest has focused on the potential role of amylin in the pathogenesis of non-insulin-dependent diabetes mellitus (NIDDM). This 37-amino acid peptide is found in extracellular amyloid deposits in approximately 50% of pancreatic islets of patients with NIDDM and has been shown to inhibit skeletal muscle glycogen synthesis in vitro. Immunocytochemical studies have colocalized amylin and insulin within beta-cell secretory granules in nondiabetic humans, provoking the following questions. Is amylin cosecreted with insulin? Are circulating amylin concentrations higher in patients with NIDDM either before or after food ingestion? To answer these questions, we developed a sensitive and specific immunoassay to measure plasma concentrations of amylin in humans. Use of this assay indicated that, in lean nondiabetic subjects, glucose ingestion resulted in an increase (P less than 0.001) in the plasma concentration of amylin (from 2.03 +/- 0.22 to 3.78 +/- 0.39 pM) and insulin (from 48.3 +/- 3.1 to 265 +/- 44 pM). There was a significant correlation between the concentrations of insulin and amylin (r = 0.74, P less than 0.001) and the increase in insulin and amylin concentration (r = 0.65, P less than 0.005). Fasting concentrations of amylin did not differ in diabetic and weight-matched nondiabetic subjects and showed a similar pattern of change after ingestion of a mixed meal. We conclude that amylin is secreted in response to ingestion of either glucose or a mixed meal and circulates at concentrations that do not differ in patients with NIDDM and nondiabetic subjects. It remains to be determined whether amylin at physiological concentrations influences carbohydrate metabolism and if so whether its effects differ in diabetic and nondiabetic humans.


Assuntos
Amiloide/sangue , Diabetes Mellitus Tipo 2/sangue , Ingestão de Alimentos , Adulto , Glicemia/análise , Humanos , Insulina/sangue , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Pessoa de Meia-Idade , Concentração Osmolar , Valores de Referência
14.
Neuroscience ; 310: 541-8, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26415767

RESUMO

Phoenixin (PNX) is a 14-amino acid amidated peptide (PNX-14) or an N-terminal extended 20-residue amidated peptide (PNX-20) recently identified in neural and non-neural tissue. Mass spectrometry analysis identified a major peak corresponding to PNX-14, with negligible PNX-20, in mouse spinal cord extracts. Using a previously characterized antiserum that recognized both PNX-14 and PNX-20, PNX-immunoreactivity (irPNX) was detected in a population of dorsal root ganglion (DRG) cells and in cell processes densely distributed to the superficial layers of the dorsal horn; irPNX cell processes were also detected in the skin. The retrograde tracer, Fluorogold, injected subcutaneously (s.c.) to the back of the cervical and thoracic spinal cord of mice, labeled a population of DRG, some of which were also irPNX. PNX-14 (2, 4 and 8 mg/kg) injected s.c.to the nape of the neck provoked dose-dependent repetitive scratching bouts directed to the back of the neck with the hindpaws. The number of scratching bouts varied from 16 to 95 in 30 min, commencing within 5 min post-injection and lasted 10-15 min. Pretreatment of mice at -20 min with nalfurafine (20 µg/kg, s.c.), the kappa opioid receptor agonist, significantly reduced the number of bouts induced by PNX-14 (4 mg/kg) compared with that of saline-pretreated mice. Our results suggest that the peptide, PNX-14, serves as one of the endogenous signal molecules transducing itch sensation in the mouse.


Assuntos
Gânglios Espinais/metabolismo , Peptídeos/metabolismo , Prurido/induzido quimicamente , Medula Espinal/metabolismo , Aminoácidos/química , Animais , Comportamento Animal/efeitos dos fármacos , Medula Cervical/metabolismo , Masculino , Camundongos , Pescoço/inervação , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/fisiologia , Pele/metabolismo
15.
Endocrinology ; 137(11): 5182-5, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8895397

RESUMO

Peptide fragments of the larger 167 amino acid obesity gene related peptide (OBGRP), leptin, were tested for their ability to inhibit feeding in the rat. The C-terminal fragment, OBGRP 116-167 exerted only minimal inhibition of feeding when administered into the lateral cerebroventricle. No alteration in feeding was observed following administration of OBGRP 57-92. We hypothesized that the satiety effects of leptin reside in the N-terminal region of the peptide sequence. Significant, dose-related, and reversible inhibition of food intake was observed following central administration of the 35 amino acid fragment OBGRP 22-56. These results suggest that a small, readily synthesized fragment of the 167 amino acid peptide leptin may exert physiologically relevant satiety effects in brain revealing an endocrine feedback mechanism by which the adipocyte may modulate hypothalamic function.


Assuntos
Ventrículos Cerebrais/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Proteínas/farmacologia , Resposta de Saciedade/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Ventrículos Cerebrais/efeitos dos fármacos , Injeções Intraventriculares , Leptina , Masculino , Dados de Sequência Molecular , Obesidade/genética , Proteínas/química , Ratos , Ratos Sprague-Dawley
16.
FEBS Lett ; 428(1-2): 59-62, 1998 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-9645475

RESUMO

Chemical synthesis of Agouti proteins - Agouti and Agouti-related proteins - is complicated by their large size and by multiple cysteine residues located in the carboxyl terminal regions. Three human Agouti-related protein (AGRP) fragments, two of which correspond to a proposed endoprotease cleavage site between amino acids 82 and 83, were synthesized and tested for anti-melanotropic activity using Xenopus laevis dermal melanophores. Amino-terminal fragments AGRP(25-51) and (54-82) were devoid of significant antagonist activity, whereas the amidated carboxyl-terminal AGRP fragment (83-132)-NH2 was potently active with an inhibitory equilibrium dissociation constant (Ki) of 0.7 nM. The ability to synthesize functionally active AGRP should help unravel its role in the central nervous system and its unusual properties with respect to interaction with the melanocortin family of G-protein coupled receptors.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular , Proteínas/farmacologia , Receptores da Corticotropina/antagonistas & inibidores , Proteína Agouti Sinalizadora , Proteína Relacionada com Agouti , Sequência de Aminoácidos , Animais , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/farmacologia , Proteínas/síntese química , Receptores de Melanocortina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Xenopus laevis
17.
Neuroscience ; 89(2): 317-21, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10077314

RESUMO

Endomorphin 1 and 2 are two tetrapeptides recently isolated from bovine as well as human brains and proposed to be the endogenous ligand for the mu-opiate receptor. Opioid compounds expressing mu-receptor preference are generally potent analgesics. The spinal cord dorsal horn is considered to be an important site for the processing of sensory information including pain. The discovery that endomorphins produced greater analgesia in mice upon intrathecal as compared to intracerebroventricular injections raises the possibility that dorsal horn neurons may represent the anatomic site upon which endomorphins exert their analgesic effects. We report here the detection of endomorphin 2-immunuoreactive fiber-like elements in superficial layers of the rat dorsal horn by immunohistochemical techniques. Whole-cell patch recordings from substantia gelatinosa neurons of cervical spinal cord slices revealed two conspicuous effects of exogenously applied endomorphin 1 and 2: (i) depression of excitatory postsynaptic potentials evoked by stimulation of dorsal root entry zone, and (ii) hyperpolarization of substantia gelatinosa neurons. These effects were reversed by the selective mu-opiate receptor antagonist beta-funaltrexamine. Collectively, the detection of endomorphin-like immunoreactivity in nerve fibers of the superficial layers and the inhibitory action of endomorphins on substantia gelatinosa neurons provide further support for a potential role of these two peptides in spinal nociception.


Assuntos
Inibição Neural/fisiologia , Neurônios/fisiologia , Oligopeptídeos/metabolismo , Medula Espinal/metabolismo , Substância Gelatinosa/fisiologia , Animais , Eletrofisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Naltrexona/análogos & derivados , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Neurônios/efeitos dos fármacos , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Substância Gelatinosa/citologia , Substância Gelatinosa/efeitos dos fármacos
18.
J Nucl Med ; 39(12): 2128-31, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9867155

RESUMO

UNLABELLED: The aim of our study was to investigate the diagnostic value of scans with 99mTc(V)-dimercaptosuccinic acid (DMSA) to localize bone and joint infection compared with scans using 67Ga. METHODS: Thirty-six patients referred for investigation of bone and joint infection were studied. In all patients, a bone scan was obtained initially. Subsequently, comparative scans with 99mTc(V)-DMSA and 67Ga were performed 1 wk apart. Microbiological findings, pathologic findings and/or clinical follow-up (until symptoms disappeared) were considered to be proof of the presence of bone and joint infection. RESULTS: Technetium-99m (V)-DMSA showed greater sensitivity and accuracy than 67Ga in the assessment of bone and joint infection, although the difference was not statistically significant. CONCLUSION: In comparison with a 67Ga scan, a 99mTc(V)-DMSA scan, in combination with a bone scan, is a reliable way to diagnose bone and joint infection. Both tracers were useful in the diagnosis of bone and joint infection.


Assuntos
Doenças Ósseas Infecciosas/diagnóstico por imagem , Doenças Transmissíveis/diagnóstico por imagem , Radioisótopos de Gálio , Artropatias/diagnóstico por imagem , Compostos Radiofarmacêuticos , Ácido Dimercaptossuccínico Tecnécio Tc 99m , Adulto , Idoso , Criança , Pré-Escolar , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
Biochem Pharmacol ; 58(6): 983-90, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10509750

RESUMO

It has been reported that nonsteroidal anti-inflammatory drugs (NSAIDs) suppress bone repair and bone remodeling but only mildly inhibit bone mineralization at the earlier stage of the repair process. We proposed that the proliferation and/or the earlier stage of differentiation of osteoblasts may be affected by NSAIDs. This study was designed to investigate whether NSAIDs affect the proliferation and/or differentiation of osteoblasts and whether these effects are prostaglandin (PG) mediated. The effects of PGE1 and PGE2, indomethacin, and ketorolac on thymidine incorporation, cell count, intracellular alkaline phosphatase (ALP) activity, and Type I collagen content in osteoblast-enriched cultures derived from fetal calvaria were evaluated. The results showed that both PGs and NSAIDs inhibited DNA synthesis and cell mitosis in a time- and concentration-dependent manner. However, intracellular ALP activity and Type I collagen content were stimulated at an earlier stage of differentiation in osteoblasts. These results suggested that (i) the inhibitory effect of ketorolac on osteoblastic proliferation contributes to its suppressive effects on bone repair and remodeling in vivo; (ii) PGEs and NSAIDs may be involved in matrix maturation and biologic bone mineralization in the earlier stage of osteoblast differentiation; and (iii) the effects of ketorolac and indomethacin on cell proliferation and differentiation may not be through the inhibition of the synthesis of PGE1 or PGE2.


Assuntos
Alprostadil/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Dinoprostona/farmacologia , Osteoblastos/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/metabolismo , Replicação do DNA/efeitos dos fármacos , Mitose/efeitos dos fármacos , Osteoblastos/enzimologia , Osteoblastos/patologia , Ratos , Ratos Sprague-Dawley
20.
Neuroreport ; 12(8): 1789-92, 2001 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-11409760

RESUMO

It has been reported that intracerebroventricular (i.c.v.) injection of nociception/orphanin FQ (OFQ) can antagonize morphine analgesia, whereas i.c.v. OFQ antibody can reverse morphine tolerance. Nocistatin (NST) is a recently characterized neuropeptide possessing an antagonizing effect on OFQ. Here we examine whether i.c.v. NST would result in a reversal of morphine tolerance. The results showed that: (1) i.c.v. NST at doses of 0.005, 0.05, 0.5, 5 or 50 ng per rat produced a bell-shaped dose-dependent reversal of chronic morphine tolerance, with maximum response at 0.5 ng. (2) Acute morphine tolerance could also be reversed, albeit partially, by i.c.v. NST at 0.5 ng. (3) The reversal of acute and chronic morphine tolerance by NST was completely abolished when NST (0.5 ng) was co-injected with (8 microg) OFQ. Since OFQ and NST are derived from the same preprohormone, the profile of its splicing in the CNS may play an important role in determining the effectiveness of morphine analgesia.


Assuntos
Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/farmacologia , Morfina/efeitos adversos , Peptídeos Opioides/farmacologia , Animais , Tolerância a Medicamentos , Injeções Intraventriculares , Masculino , Peptídeos Opioides/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Nociceptina
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