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1.
Biosens Bioelectron ; 261: 116466, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38850736

RESUMO

Human breath contains biomarkers (odorants) that can be targeted for early disease detection. It is well known that honeybees have a keen sense of smell and can detect a wide variety of odors at low concentrations. Here, we employ honeybee olfactory neuronal circuitry to classify human lung cancer volatile biomarkers at different concentrations and their mixtures at concentration ranges relevant to biomarkers in human breath from parts-per-billion to parts-per-trillion. We also validated this brain-based sensing technology by detecting human non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) cell lines using the 'smell' of the cell cultures. Different lung cancer biomarkers evoked distinct spiking response dynamics in the honeybee antennal lobe neurons indicating that those neurons encoded biomarker-specific information. By investigating lung cancer biomarker-evoked population neuronal responses from the honeybee antennal lobe, we classified individual human lung cancer biomarkers successfully (88% success rate). When we mixed six lung cancer biomarkers at different concentrations to create 'synthetic lung cancer' vs. 'synthetic healthy' human breath, honeybee population neuronal responses were able to classify those complex breath mixtures reliably with exceedingly high accuracy (93-100% success rate with a leave-one-trial-out classification method). Finally, we employed this sensor to detect human NSCLC and SCLC cell lines and we demonstrated that honeybee brain olfactory neurons could distinguish between lung cancer vs. healthy cell lines and could differentiate between different NSCLC and SCLC cell lines successfully (82% classification success rate). These results indicate that the honeybee olfactory system can be used as a sensitive biological gas sensor to detect human lung cancer.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , Neoplasias Pulmonares , Olfato , Humanos , Animais , Neoplasias Pulmonares/patologia , Abelhas , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Olfato/fisiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Odorantes/análise , Testes Respiratórios/métodos , Testes Respiratórios/instrumentação , Carcinoma de Pequenas Células do Pulmão/patologia , Compostos Orgânicos Voláteis/análise
2.
Methods Mol Biol ; 2592: 185-194, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36507994

RESUMO

Human islet transplantation is a promising therapy to restore normoglycemia for type 1 diabetes (T1D). Despite recent advances, human islet transplantation remains suboptimal due to significant islet graft loss after transplantation. Various immunological and nonimmunological factors contribute to this loss therefore signifying a need for strategies and approaches for visualizing and monitoring transplanted human islet grafts. One such imaging approach is magnetic particle imaging (MPI), an emerging imaging modality that detects the magnetization of iron oxide nanoparticles. MPI is known for its specificity due to its high image contrast and sensitivity. MPI through its noninvasive nature provides the means for monitoring transplanted human islets in real time. Here we summarize an approach to track transplanted human islets using MPI. We label human islet from donors with dextran-coated ferucarbotran iron oxide nanoparticles, transplant the labeled human islet into under the left kidney capsule, and image graft cells using an MPI scanner. We engineer a K-means++, clustering-based unsupervised machine learning algorithm for standardized image segmentation and iron quantification of the MPI, which solves problems with selection bias and indiscriminate signal boundary that accompanies this newer imaging modality. In this chapter, we summarize the methods of this emerging imaging modality of MPI in conjunction with unsupervised machine learning to monitor and visualize islets after transplantation.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Humanos , Ilhotas Pancreáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Transplante das Ilhotas Pancreáticas/métodos , Aprendizado de Máquina , Fenômenos Magnéticos
3.
Pest Manag Sci ; 77(8): 3698-3705, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33442945

RESUMO

BACKGROUND: Insects rely on their sense of smell to locate food and hosts, find mates and select sites for laying eggs. Use of volatile compounds, such as essential oils (EOs), to repel insect pests and disrupt their olfaction-driven behaviors has great practical significance in integrated pest management. However, our knowledge on the olfaction-based mechanisms of EO repellency is quite limited. RESULTS: We evaluated the repellency of peppermint oil and nine plant EO components in Drosophila melanogaster, a model insect for olfaction study, and D. suzukii, a major fruit crop pest. All nine volatiles, menthone, (-)-menthol, menthyl acetate, (R)-(+)-limonene, nerol, (+)-fenchone, (-)-α-thujone, camphor, norcamphor and peppermint oil, elicited repellency in D. melanogaster in a dose-dependent manner. Most of the compounds, except camphor, also elicited repellency in D. suzukii. Menthone, (R)-(+)-limonene and (+)-fenchone were the most potent repellents against D. suzukii. Repellency was reduced or abolished in two D. melanogaster mutants of the odorant receptor co-receptor (Orco), indicating that the observed repellency is odorant receptor (Or)-mediated. Repellency by peppermint oil, menthone, (R)-(+)-limonene, (-)-α-thujone and norcamphor also involves Or-independent mechanism(s). Single sensillum recording from both species revealed that common and distinct Ors and olfactory receptor neurons were activated by these compounds. CONCLUSIONS: The tested plant EO components evoke repellency by activating multiple Ors in both Drosophila species. Our study provides a foundation for further elucidation of the mechanism of EOs repellency and species-specific olfactory adaptations. © 2021 Society of Chemical Industry.


Assuntos
Repelentes de Insetos , Óleos Voláteis , Receptores Odorantes , Animais , Drosophila , Drosophila melanogaster , Óleos de Plantas
4.
Pharmacol Res Perspect ; 8(4): e00613, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32567817

RESUMO

Osimertinib is a third-generation, irreversible, oral epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) that potently and selectively inhibits both EGFR-TKI sensitizing and EGFR T790M and has demonstrated efficacy in non-small cell lung cancer (NSCLC) central nervous system metastases. In this phase I study, we assessed the effects of normal renal function (NRF) and severe renal impairment (SRI) on the pharmacokinetics (PK) of osimertinib in patients with solid tumors. Part A: patients with NRF (creatinine clearance [CrCL] ≥90 mL/min), and SRI, (CrCL <30 mL/min), received a single 80-mg oral dose of osimertinib and standard PK measures were assessed. Part B: patients with SRI were treated for 3 months to obtain safety data, if deemed clinically appropriate. The geometric mean osimertinib plasma concentrations were higher in patients with SRI (n = 7) vs NRF (n = 8) and were highly variable. Osimertinib exposure based on Cmax and area under the plasma concentration-time curve, was 1.19-fold (90% CI: 0.6, 2.0) and 1.85-fold (90% CI: 0.9, 3.6), respectively, higher for patients with SRI vs patients with NRF, with no clear correlation between CrCL and exposure. No new safety signals were identified after 12 weeks of osimertinib 80 mg continuous dosing. PK parameters pooled across this study and other phase I, II, and III osimertinib clinical studies (exploratory population PK analysis), showed minimal correlation between CrCL and total clearance. In conclusion, no dose adjustment is required for osimertinib for patients with SRI.


Assuntos
Acrilamidas/farmacocinética , Compostos de Anilina/farmacocinética , Insuficiência Hepática/complicações , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacocinética , Acrilamidas/administração & dosagem , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina/administração & dosagem , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Área Sob a Curva , Feminino , Insuficiência Hepática/fisiopatologia , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/administração & dosagem , Índice de Gravidade de Doença
5.
Gastroenterol Hepatol ; 41(3): 153-162, 2018 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29279233

RESUMO

OBJECTIVES: To identify glutamic pyruvic transaminase (GPT) and hepatitis B virus DNA (HBV-DNA) cut-off values at diagnosis in patients with hepatitis B virus e antigen-negative chronic infection (HBeAg(-)), which may be predictors of clinical course, prognosis and/or the need for antiviral therapy. METHODS: A retrospective and observational cohort study of patients diagnosed with HBeAg(-) chronic infection (2005-2012). A normal GPT cut-off value at diagnosis that predicts abnormal GPT values in the clinical course of the infection, a baseline HBV-DNA cut-off value that predicts an increase in HBV-DNA above 2,000IU/ml, and GPT and HBV-DNA as predictors of the need for treatment were investigated using ROC curves. RESULTS: 126 patients were enrolled (follow-up: 42.1±21.5months), 93 of which had normal GPT levels at diagnosis. In the ROC curve analysis, 900IU/ml was found to be the HBV-DNA cut-off value that best predicted this value's increase above 2,000IU/ml (sensitivity: 90%; specificity: 88%; PPV: 79%; NPV: 100%; diagnostic precision: 89%), while 25mU/ml was the normal GPT cut-off value at diagnosis that best predicted subsequently elevated GPT levels (sensitivity: 95.4%; specificity: 81.6%; PPV: 67%; NPV: 96%; diagnostic precision: 80.6%). Patients with GPT 26-40mU/ml at diagnosis presented with more complications or required more treatment than subjects with GPT≤25mU/ml (P<.05). The combined GPT and HBV-DNA values that elicited the highest treatment need were 38mU/ml of GPT and 6,000IU/ml of HBV-DNA (sensitivity: 75%; specificity: 93.4%; PPV: 60%; NPV: 96.6%). CONCLUSION: HBeAg(-) patients with GPT<25mU/ml and HBV-DNA<900IU/ml at diagnosis have positive outcomes and may not require such stringent follow-up in the first years after diagnosis.


Assuntos
Alanina Transaminase/sangue , DNA Viral/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Adulto , Estudos de Coortes , Feminino , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos
6.
Gastroenterol Hepatol ; 40(2): 59-69, 2017 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28007350

RESUMO

OBJECTIVE: To describe the epidemiological, analytical and histological characteristics and clinical course of hepatitis B virus (HBV) carriers with negative HBe antigen. MATERIAL AND METHODS: Observational, retrospective cohort study of HBV carriers with negative HBe antigen (2005-2012), with no other causes of liver disease. RESULTS: One hundred and thirty-eight patients were included, with mean age 40.5±12.2 years; 54% were women, and 38% were of foreign origin; the number of foreign patients significantly increased (P<.001) over the years. Transaminases were normal in nearly 75% and HBV-DNA was <2,000IU/ml in 56% of patients at diagnosis. There was a gradual decrease in HBV-DNA levels in inactive carriers over the study period. Fibrosis study was performed in 47% of patients by Fibroscan® or liver biopsy: 55.4% normal histology and 6.1% cirrhosis. Just over three quarters of patients (77.77%) were inactive carriers. Treatment was required in 15.5% of patients (20% because of cirrhosis and 80% HBeAg-negative chronic hepatitis B). Five patients cleared HBsAg (annual rate .94%), all of whom presented HBV-DNA <2,000IU/ml at diagnosis. Five patients developed complications (3.6%), 4 of them hepatocellular carcinoma (HCC), of which only 2 had cirrhosis. There was 1 HBV-related death (.72%). CONCLUSION: Among HBV carriers with negative HBe antigen, inactive HBs-Ag carriers are predominant. HBV-DNA gradually decreases in the first few years after diagnosis. Morbidity and mortality are low, especially if glutamic pyruvic transaminase (GPT) is normal and HBV-DNA levels are low at diagnosis. Treatment is needed in a considerable number of patients. HCC is the most frequent complication, even in the absence of cirrhosis.


Assuntos
Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Adulto , Estudos de Coortes , Feminino , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/epidemiologia , Humanos , Masculino , Estudos Retrospectivos
8.
Forensic Sci Int Genet ; 7(1): 10-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22613778

RESUMO

The GHEP-ISFG Working Group performed a collaborative exercise to monitor the current practice of mitochondrial (mt)DNA reporting. The participating laboratories were invited to evaluate a hypothetical case example and assess the statistical significance of a match between the haplotypes of a case (hair) sample and a suspect. A total of 31 forensic laboratories participated of which all but one used the EMPOP database. Nevertheless, we observed a tenfold range of reported LR values (32-333.4), which was mainly due to the selection of different reference datasets in EMPOP but also due to different applied formulae. The results suggest the need for more standardization as well as additional research to harmonize the reporting of mtDNA evidence.


Assuntos
DNA Mitocondrial/genética , Bases de Dados Genéticas , Haplótipos , Humanos
9.
PLoS One ; 7(11): e50885, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226419

RESUMO

Prenatal exposure to cocaine, in mammals, has been shown to interfere with the expression of opioid receptors, which can have repercussions in its activity. Likewise, microRNAs, such as let-7, have been shown to regulate the expression of opioid receptors and hence their functions in mammals and in vitro experiments. In light of this, using the zebrafish embryos as a model our aim here was to evaluate the actions of cocaine in the expression of opioid receptors and let-7d miRNA during embryogenesis. In order to determine the effects produced by cocaine on the opioid receptors (zfmor, zfdor1 and zfdor2) and let-7d miRNA (dre-let-7d) and its precursors (dre-let-7d-1 and dre-let-7d-2), embryos were exposed to 1.5 µM cocaine hydrochloride (HCl). Our results revealed that cocaine upregulated dre-let-7d and its precursors, and also increased the expression of zfmor, zfdor1 and zfdor2 during early developmental stages and decreased them in late embryonic stages. The changes observed in the expression of opioid receptors might occur through dre-let-7d, since DNA sequences and the morpholinos of opioid receptors microinjections altered the expression of dre-let-7d and its precursors. Likewise, opioid receptors and dre-let-7d showed similar distributions in the central nervous system (CNS) and at the periphery, pointing to a possible interrelationship between them.In conclusion, the silencing and overexpression of opioid receptors altered the expression of dre-let-7d, which points to the notion that cocaine via dre-let-7 can modulate the expression of opioid receptors. Our study provides new insights into the actions of cocaine during zebrafish embryogenesis, indicating a role of miRNAs, let-7d, in development and its relationship with gene expression of opioid receptors, related to pain and addiction process.


Assuntos
Cocaína/farmacologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , MicroRNAs/genética , Receptores Opioides/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Absorção , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , MicroRNAs/biossíntese , MicroRNAs/metabolismo , Microinjeções , Modelos Biológicos , Morfolinos/farmacologia , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Opioides/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
10.
PLoS One ; 7(12): e52701, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23285158

RESUMO

The use of cocaine during pregnancy can affect the mother and indirectly might alter the development of the embryo/foetus. Accordingly, in the present work our aim was to study in vivo (in zebrafish embryos) the effects of cocaine on the expression of dopamine receptors and on miR-133b. These embryos were exposed to cocaine hydrochloride (HCl) at 5 hours post-fertilization (hpf) and were then collected at 8, 16, 24, 48 and 72 hpf to study the expression of dopamine receptors, drd1, drd2a, drd2b and drd3, by quantitative real time PCR (qPCR) and in situ hybridization (ISH, only at 24 hpf). Our results indicate that cocaine alters the expression of the genes studied, depending on the stage of the developing embryo and the type of dopamine receptor. We found that cocaine reduced the expression of miR-133b at 24 and 48 hpf in the central nervous system (CNS) and at the periphery by qPCR and also that the spatial distribution of miR-133b was mainly seen in somites, a finding that suggests the involvement of miR-133b in the development of the skeletal muscle. In contrast, at the level of the CNS miR-133b had a weak and moderate expression at 24 and 48 hpf. We also analysed the interaction of miR-133b with the Pitx3 and Pitx3 target genes drd2a and drd2b, tyrosine hydroxylase (th) and dopamine transporter (dat) by microinjection of the Pitx3-3'UTR sequence. Microinjection of Pitx3-3'UTR affected the expression of pitx3, drd2a, drd2b, th and dat. In conclusion, in the present work we describe a possible mechanism to account for cocaine activity by controlling miR-133b transcription in zebrafish. Via miR-133b cocaine would modulate the expression of pitx3 and subsequently of dopamine receptors, dat and th. These results indicate that miRNAs can play an important role during embryogenesis and in drug addiction.


Assuntos
Cocaína/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , MicroRNAs/genética , Receptores Dopaminérgicos/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cocaína/administração & dosagem , Feminino , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Modelos Biológicos , Filogenia , Gravidez , Receptores Dopaminérgicos/metabolismo , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
11.
Neuroscience ; 200: 237-47, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22062135

RESUMO

Opioids are the most potent analgesics known today, but their prolonged administration produces severe adverse effects such as constipation, bradycardia, besides addiction, a concept not fully understood at present, which represents one of the most important challenges of modern bioscience. Wnts constitute an important family of vertebrate genes that encode secreted signaling proteins implicated in various developmental processes (patterning of the neural tube, neuronal differentiation), and are extensively conserved through evolution. In this study we have focused on Wnt1, an essential signal in axis polarity, as well as in proliferation and the development and differentiation of the CNS, roles shared by opioid receptors. Our previous studies in zebrafish show that morphine, the most potent analgesic known today, increases cell proliferation and induces neuronal protection and dopaminergic differentiation by activating the opioid receptors. The aim of the present study is to determine whether these effects are a consequence of an interaction between Wnt1 and the endogenous opioid system, which may act as a transcription regulator of Wnt1. Hence, we have exposed embryos to morphine, the endogenous delta opioid agonist Met-Enkephalin-Glu-Tyr (MEGY) (it binds with high affinity to both zebrafish delta opioid receptors, ZfDORs), and SNC80, a highly specific delta agonist, which displays low affinity towards the ZfDORs. Although at earlier stages, all opioids reduced the expression level of Wnt1, further on development, mainly during the differentiation of the CNS (24-48 h post fertilization (hpf)), morphine and MEGY increased Wnt1 expression. Our results point to the possibility that opioid signaling controls the transcription of Wnt1 and that through Wnt1, the opioid system regulates cell proliferation and neuronal differentiation. The present work opens a door to the discovery of new mechanisms that regulate opioid activity and its adverse effects, and hence, it might provide a good target to design new drugs that prevent or avoid these effects.


Assuntos
Analgésicos Opioides/farmacologia , Embrião não Mamífero/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteína Wnt1/metabolismo , Fatores Etários , Análise de Variância , Animais , Benzamidas/farmacologia , Interações Medicamentosas , Embrião não Mamífero/anatomia & histologia , Embrião não Mamífero/metabolismo , Encefalina Metionina/análogos & derivados , Encefalina Metionina/farmacologia , Morfina/farmacologia , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Piperazinas/farmacologia , Receptores Opioides delta/metabolismo , Proteína Wnt1/genética , Peixe-Zebra/embriologia
12.
J Mol Endocrinol ; 46(2): 111-23, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21247980

RESUMO

The nociceptin receptor (NOP) and its endogenous ligand, nociceptin/orphanin FQ (OFQ), are involved in a wide range of biological functions, such as pain, anxiety, learning, and memory. The zebrafish has been proposed as a candidate to study the in vivo effects of several drugs of abuse and to discover new pharmacological targets. We report the cloning, expression, and pharmacological characterization of a NOP receptor from zebrafish (drNOP). The full-length cDNA codes a protein of 363 residues, which shows high sequence similarity to other NOPs. Phylogenetic analysis indicates that NOPs are broadly conserved during vertebrate evolution, and that they stand for the most divergent clade of the opioid/OFQ receptor family. Expression studies have revealed that drNOP mRNA is highly expressed in the central nervous system, and low expression levels are also found in peripheral tissues such as gills, muscle, and liver. Pharmacological analysis indicates that drNOP displays specific and saturable binding for [Leucyl-3,4,5-(3)H]nociceptin, with a K(d)=0.20 ± 0.02 nM and a B(max)=1703 ± 81 fmol/mg protein. [(3)H]Nociceptin binding is displaced by several opioid ligands such as dynorphin A (DYN A), naloxone, bremazocine, or the κ-selective antagonist nor-binaltorphimine. [(35)S]GTPγS stimulation studies showed that drNOP receptor is functional, as nociceptin is able to fully activate the receptor and DYN A behaves as a partial agonist (50% stimulation). Our results indicate that drNOP receptor displays mixed characteristics of both NOP and κ opioid receptors. Hence, drNOP, which has retained more of the likely ancestral features, bridges the gap between nociceptin and opiate pharmacology.


Assuntos
Peptídeos Opioides/farmacologia , Ligação Proteica/efeitos dos fármacos , Receptores Opioides , Proteínas Recombinantes/metabolismo , Sequência de Aminoácidos , Animais , Química Encefálica , Clonagem Molecular , DNA Complementar , Expressão Gênica , Brânquias/química , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Células HEK293 , Humanos , Cinética , Fígado/química , Modelos Animais , Dados de Sequência Molecular , Peptídeos Opioides/metabolismo , Filogenia , Ligação Proteica/fisiologia , Receptores Opioides/genética , Receptores Opioides/isolamento & purificação , Receptores Opioides/metabolismo , Receptores Opioides kappa/genética , Receptores Opioides kappa/metabolismo , Proteínas Recombinantes/genética , Alinhamento de Sequência , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Receptor de Nociceptina , Nociceptina
14.
Mol Pharmacol ; 78(5): 935-42, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20716624

RESUMO

Morphine is one of the analgesics used most to treat chronic pain, although its long-term administration produces tolerance and dependence through neuronal plasticity. The ability of morphine to regulate neuron differentiation in vivo has been reported. However, the detailed mechanisms have not yet been elucidated because of the inability to separate maternal influences from embryonic events. Using zebrafish embryos as the model, we demonstrate that morphine decreases miR-133b expression, hence increasing the expression of its target, Pitx3, a transcription factor that activates tyrosine hydroxylase and dopamine transporter. Using a specific morpholino to knock down the zebrafish µ-opioid receptor (zfMOR) in the embryos and selective mitogen-activated protein kinase inhibitors, we demonstrate that the morphine-induced miR-133b decrease in zebrafish embryos is mediated by zfMOR activation of extracellular signal-regulated kinase 1/2. A parallel morphine-induced down-regulation of miR-133b was observed in the immature but not in mature rat hippocampal neurons. Our results indicate for the first time that zebrafish embryos express a functional µ-opioid receptor and that zebrafish serves as an excellent model to investigate the roles of microRNA in neuronal development affected by long-term morphine exposure.


Assuntos
Analgésicos Opioides/farmacologia , Dopamina/metabolismo , MicroRNAs/fisiologia , Morfina/farmacologia , Neurônios/efeitos dos fármacos , Animais , Diferenciação Celular , Células Cultivadas , Embrião não Mamífero , Ativação Enzimática , Regulação da Expressão Gênica , Inativação Gênica , Hipocampo/citologia , Hipocampo/metabolismo , MicroRNAs/biossíntese , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Receptores Opioides mu/genética , Receptores Opioides mu/fisiologia , Transdução de Sinais , Peixe-Zebra
15.
Eur J Neurosci ; 32(4): 550-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20646065

RESUMO

Morphine remains one of the most potent analgesic compounds used to control chronic pain despite its known adverse effects. It binds to the opioid receptors mu, delta and kappa, which are involved in aspects of neuronal fate such as cell proliferation, neuroprotection and neuronal differentiation. However, the effect of morphine on these processes is controversial and in vitro studies, as well as in vivo studies on adults and neonates in mammalian models, have not been able to clarify the diverse roles of morphine in the central nervous system. We have used zebrafish embryos to determine in vivo how morphine affects neuronal fate and opioid receptor gene expression and to elucidate if there is a link between these processes. Our results show that at 24 and 48 h post fertilization (hpf) morphine enhances cell proliferation, although it has opposing effects as an inducer of neuronal differentiation at these two stages, increasing the number of certain neuronal populations at 24 hpf and decreasing it at 48 hpf. The present study also demonstrates that in 24-hpf embryos morphine acts as a neuroprotector against glutamate damage in motor neurons and Pax-6-positive neurons. Furthermore, the gene expression of the opioid receptors is altered by embryonic exposition to morphine. In conclusion, our study sheds new light on the in vivo roles of morphine, and it indicates for the first time that its implication in cell proliferation and neuroprotection might be related to changes in the gene expression of opioid receptors.


Assuntos
Analgésicos Opioides/farmacologia , Embrião não Mamífero/efeitos dos fármacos , Morfina/farmacologia , Neurônios/efeitos dos fármacos , Receptores Opioides/metabolismo , Peixe-Zebra/embriologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Embrião não Mamífero/anatomia & histologia , Embrião não Mamífero/metabolismo , Ácido Glutâmico/metabolismo , Neurônios/citologia , Neurônios/fisiologia , Peixe-Zebra/anatomia & histologia , Peixe-Zebra/metabolismo
16.
Int J Dev Neurosci ; 27(4): 315-20, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19460625

RESUMO

The NOP system is considered to be part of the opioid system, although it exerts antiopioid actions depending on the anatomical region where it is localized. This apparent controversy has lead to the hypothesis that the NOP system interacts with the classical opioid systems (mu, delta, kappa) and regulates/modulates their activity in relation to analgesia and the development of addiction to drugs. In order to shed light into the importance of the NOP system, we have analyzed the expression of NOP during zebrafish development, and the effect of its endogenous agonist nociceptin and the opioid agonist morphine on NOP expression. Our qPCR study show that the number of NOP transcripts is different at each developmental stage studied (0.5 hpf, 2.75 hpf, 3 hpf, 8 hpf, 16 hpf, 19 hpf, 22 hpf, 24 hpf, 30 hpf, 48 hpf, 60 hpf and 72 hpf). Nociceptin enhances NOP expression at 24 hpf but decreases the number of NOP copies at 48 hpf, whereas NOP expression decreases after morphine exposure at 24 hpf and 48 hpf. Also, our ISH analysis demonstrates that nociceptin causes a change in the distribution of NOP towards rostral areas at both developmental stages. Morphine produces similar changes to those of nociceptin although only at 48 hpf. The present work leads to the conclusion that the NOP system is important during embryogenesis. Exposure to drugs changes the expression level and localization of NOP, suggesting that also during development, NOP plays a role in the apparition of dependence and addiction to drugs.


Assuntos
Analgésicos Opioides/metabolismo , Morfina/metabolismo , Peptídeos Opioides/metabolismo , Receptores Opioides/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/crescimento & desenvolvimento , Animais , Encéfalo/anatomia & histologia , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Receptores Opioides/genética , Peixe-Zebra/anatomia & histologia , Peixe-Zebra/genética , Receptor de Nociceptina , Nociceptina
18.
Neuroscience ; 151(1): 129-37, 2008 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-18082336

RESUMO

Zebrafish is a novel experimental model that has been used in developmental studies as well as in the study of pathological processes involved in human diseases. It has been demonstrated that the endogenous opioid system is involved in developmental mechanisms. We have studied the relationship between the different embryonic stages and opioid receptor expression for the four known opioid receptors in zebrafish (mu, delta 1, delta 2 and kappa). The mu opioid receptor is detected at higher levels than the other opioid receptors before the midblastula transition and during the segmentation period. The delta duplicate 2 exhibits only one peak of expression at 21 h postfertilization (hpf), when the motor nervous system is forming. The kappa receptor is expressed at very low levels. In situ hybridization studies at 24 hpf show that the opioid receptors are widely distributed in zebrafish CNS and at 48 hpf their localization is detected in more defined structures. Our results support specific implications of the opioid receptors in developmental processes such as morphogenesis of the CNS, neurogenesis, neuroprotection and development of neuromuscular and digestive system. Pain-related alterations can be a consequence of changes in the endogenous opioid system during development, hence we provide important information that might help to solve pain-related pathological situations.


Assuntos
Envelhecimento/metabolismo , Receptores Opioides/biossíntese , Receptores Opioides/metabolismo , Actinas/biossíntese , Actinas/genética , Animais , Química Encefálica/genética , Química Encefálica/fisiologia , Clonagem Molecular , DNA Complementar/biossíntese , DNA Complementar/genética , Embrião não Mamífero , Hibridização In Situ , RNA/biossíntese , RNA/isolamento & purificação , Receptores Opioides delta/biossíntese , Receptores Opioides delta/genética , Receptores Opioides kappa/biossíntese , Receptores Opioides kappa/genética , Receptores Opioides mu/biossíntese , Receptores Opioides mu/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual , Peixe-Zebra
20.
Rev Esp Enferm Dig ; 97(1): 7-15, 2005 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-15801893

RESUMO

INTRODUCTION: Aneuploidy has been observed in 6-27% of lesions known to be precursors of colorectal cancer, such as adenomas or ulcerative colitis. It has been suggested that aneuploidy may predispose to malignancy in these cases. However, its role in the adenoma-carcinoma sequence has not been definitely established. The objective of this study was to assess the incidence of aneuploidy in colon adenomas, as well as to study its possible role in the adenoma-carcinoma sequence. MATERIAL AND METHODS: The study was performed on a series of 57 large bowel adenomas measuring 10 mm or more, collected from 54 consecutive patients. All specimens were obtained either by endoscopic or by surgical resection. There were 49 adenomas with low-grade dysplasia, two with high-grade dysplasia, two intramucous carcinomas, and four microinvasive carcinomas. A flow cytometric DNA analysis was performed in fresh specimens following Vindelov's method. RESULTS: Aneuploid DNA was detected in five out of 49 low-grade dysplasia adenomas (10%), in all four high-grade dysplasia adenomas or intramucous carcinomas (100%), and in three out of four microinvasive carcinomas (75%). The association between aneuploidy and high-grade dysplasia adenomas, intramucous, or microinvasive carcinoma was statistically significant (p < 0.001). No association was found between aneuploidy and any of the following features: age, gender, clinical symptoms of patients, and size or location of adenomas. CONCLUSIONS: The incidence of aneuploidy in this series was 10% in low-grade dysplasia adenomas, and 87% in high-grade dysplasia adenomas or carcinomas, and this difference was statistically significant. These findings suggest that aneuploidy may play a role in the adenoma-carcinoma sequence.


Assuntos
Adenoma/genética , Aneuploidia , Neoplasias Colorretais/genética , Lesões Pré-Cancerosas/genética , Adenoma/patologia , Idoso , Neoplasias Colorretais/patologia , DNA/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia
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