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1.
Artigo em Inglês | MEDLINE | ID: mdl-38729747

RESUMO

BACKGROUND: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a peripheral nerve disorder characterised by weakness and sensory loss. We assessed the neonatal Fc receptor inhibitor rozanolixizumab for CIDP management. METHODS: CIDP01 (NCT03861481) was a randomised, subject-blind, investigator-blind, placebo-controlled, phase 2a study. Adults with definite or probable CIDP receiving subcutaneous or intravenous immunoglobulin maintenance therapy were randomised 1:1 to 12 once-weekly subcutaneous infusions of rozanolixizumab 10 mg/kg or placebo, stratified according to previous immunoglobulin administration route. Investigators administering treatment and assessing efficacy, and patients, were blinded. The primary outcome was a change from baseline (CFB) to day 85 in inflammatory Rasch-built Overall Disability Scale (iRODS) score. Eligible patients who completed CIDP01 entered the open-label extension CIDP04 (NCT04051944). RESULTS: In CIDP01, between 26 March 2019 and 31 March 2021, 34 patients were randomised to rozanolixizumab or placebo (17 (50%) each). No significant difference in CFB to day 85 in iRODS centile score was observed between rozanolixizumab (least squares mean 2.0 (SE 3.2)) and placebo (3.4 (2.6); difference -1.5 (90% CI -7.5 to 4.5)). Overall, 14 (82%) patients receiving rozanolixizumab and 13 (76%) receiving placebo experienced a treatment-emergent adverse event during the treatment period. Across CIDP01 and CIDP04, rozanolixizumab was well tolerated over up to 614 days; no clinically meaningful efficacy results were seen. No deaths occurred. CONCLUSIONS: Rozanolixizumab did not show efficacy in patients with CIDP in this study, although this could be due to a relatively high placebo stability rate. Rozanolixizumab was well tolerated over medium-to-long-term weekly use, with an acceptable safety profile.

2.
J Appl Toxicol ; 42(8): 1337-1353, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35146777

RESUMO

Aluminum (Al), a common light metal, affects the developing nervous system. Developmental exposure to Al chloride (AlCl3 ) induces aberrant neurogenesis by targeting neural stem cells (NSCs) and/or neural progenitor cells (NPCs) in the dentate gyrus (DG) of rats and mice. To investigate whether hippocampal neurogenesis is similarly affected by AlCl3 exposure in a general toxicity study, AlCl3 was orally administered to 5-week-old Sprague Dawley rats at dosages of 0, 4000, or 8000 ppm in drinking water for 28 days. AlCl3 downregulated Sox2 transcript level in the DG at the highest dosage and produced a dose-dependent decrease of SOX2+ cells without altering numbers of GFAP+ or TBR2+ cells in the subgranular zone, suggesting that AlCl3 decreases Type 2a NPCs. High-dose exposure downregulated Pcna, upregulated Pvalb, and altered expression of genes suggestive of oxidative stress induction (upregulation of Nos2 and downregulation of antioxidant enzyme genes), indicating suppressed proliferation and differentiation of Type 1 NSCs. AlCl3 doses also increased mature granule cells in the DG. Upregulation of Reln may have contributed to an increase of granule cells to compensate for the decrease of Type 2a NPCs. Moreover, upregulation of Calb2, Gria2, Mapk3, and Tgfb3, as well as increased numbers of activated astrocytes in the DG hilus, may represent ameliorating responses against suppressed neurogenesis. These results suggest that 28-day exposure of young-adult rats to AlCl3 differentially targeted NPCs and mature granule cells in hippocampal neurogenesis, yielding a different pattern of disrupted neurogenesis from developmental exposure.


Assuntos
Células-Tronco Neurais , Neurogênese , Cloreto de Alumínio/toxicidade , Animais , Proliferação de Células , Giro Denteado/metabolismo , Hipocampo , Camundongos , Células-Tronco Neurais/metabolismo , Ratos , Ratos Sprague-Dawley
3.
Artigo em Inglês | MEDLINE | ID: mdl-38937404

RESUMO

INTRODUCTION: Certolizumab pegol (CZP) is an anti-tumor necrosis factor alpha (TNFα) approved for the treatment of moderate to severe plaque psoriasis (PSO). However, data on its real-world use is currently limited. The objective of this study was to describe the 1-year real-world effectiveness of CZP, its impact on health-related quality of life (HRQoL), and safety outcomes in patients with moderate to severe PSO in multi-country settings. METHODS: CIMREAL, a prospective, noninterventional study, was conducted across Europe and Canada from August 2019 to December 2022. Patients were followed for 1-year, receiving CZP 400 mg initial doses at weeks 0, 2, and 4, followed by CZP 200 mg every 2 weeks (Q2W) or CZP 400 mg Q2W maintenance dosing. Effectiveness was assessed using the Psoriasis Area and Severity Index (PASI) and Dermatology Life Quality Index (DLQI). Safety was also evaluated. RESULTS: Overall, 399 patients with moderate to severe PSO were included. Of these, 93.7% (374/399) and 77.9% (311/399) completed months 3 and 12, respectively. Mean age (± standard deviation) was 42.9 ± 13.5 years and body mass index was 28.5 ± 6.8 kg/m2, with the majority of patients being female (68.2%). At 12 months, CZP showed substantial effectiveness, achieving PASI 75 and PASI 90 response rates (≥ 75% and ≥ 90% improvement from baseline, respectively) of 77% and 56.5%, respectively. Patients with PASI score of ≤ 3 and ≤ 2 experienced improvement from 3 months (49.8% and 41.1%, respectively) to 12 months (82.0% and 75.3%, respectively). HRQoL considerably improved, with mean DLQI scores decreasing from 12.4 to 2.3 after 12 months of treatment, and the proportion of patients with DLQI 0/1 increased from 28.6% at 3 months to 59.4% at 12 months. The 1-year probability of persistence was approximately 85%. Overall, 30.6% of the patients experienced any adverse events and 9.3% had serious adverse events. CONCLUSION: In routine clinical practice, CZP exhibited consistent effectiveness, positively impacting both skin psoriasis activity and HRQoL. The 1-year persistence of CZP was high, and no new safety signals were identified. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT04053881 https://www. CLINICALTRIALS: gov/study/NCT04053881 .

4.
Food Chem Toxicol ; 173: 113607, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36657701

RESUMO

We investigated the role of endoplasmic reticulum (ER)-phagy in NAFLD-related hepatocarcinogenesis in high-fat diet (HFD)-fed and/or phenobarbital (PB)-treated rats by clustering the expression levels of the selective autophagy receptor p62 and the ER-phagy-specific receptor FAM134B in preneoplastic hepatic lesions. We obtained four clusters with variable expression levels of p62 and FAM134B in preneoplastic lesions, and a variable population of clusters in each group. PB administration increased the clusters with high expression levels of p62 while HFD feeding increased the clusters with high expression levels of both p62 and FAM134B. The areas of preneoplastic lesions of these clusters were significantly increased than those of other clusters with low expression levels of p62 and FAM134B. The combination of HFD feeding with PB counteracted the effects of each other, and the cluster composition was similar to that in the control group. The results were associated with decreased gene expression of ER stress, inflammatory cytokine, autophagy, and increased expression of antioxidant enzyme. The present study demonstrated that clustering analysis is useful for understanding the role of autophagy in each preneoplastic lesion, and that HFD feeding increased preneoplastic lesions through the inhibition of ER-phagy, which was cancelled with PB administration through the induction of ER-phagy.


Assuntos
Dieta Hiperlipídica , Proteínas de Membrana , Ratos , Animais , Proteínas de Membrana/metabolismo , Dieta Hiperlipídica/efeitos adversos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Autofagia , Proteínas de Transporte/metabolismo
5.
Toxicol Lett ; 390: 33-45, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37926403

RESUMO

We previously performed comprehensive analyses of genes hypermethylated promoter regions and downregulated transcripts in the hippocampal dentate gyrus (DG) of rats upon weaning at postnatal day (PND) 21 after developmental exposure to 6-propyl-2-thiouracil (PTU), valproic acid, and glycidol (GLY), all of which are known to show irreversible effects on hippocampal neurogenesis in adulthood on PND 77. Here, we selected neurotransmitter and neurogenesis-related genes for validation analysis of methylation and expression. As a result, Nrgn by GLY and Shisa7, Agtpbp1, and Cyp46a1 by PTU underwent DNA hypermethylation and sustained downregulation. Immunohistochemical analysis of candidate gene products revealed that the number of neurogranin (NRGN)+ granule cells was decreased in the ventral DG by GLY on PND 21 and 77 and by PTU on PND 21. Among the samples of developmental or 28-day young adult-age exposure to known developmental neurotoxicants in humans, i.e., lead acetate, ethanol, and aluminum chloride, a decrease of NRGN+ cells by ethanol was also observed on PND 77 after developmental exposure. Double immunohistochemistry analysis revealed that NRGN was expressed in mature granule cells, and a similar immunoreactive cell distribution was found for phosphorylated calcium/calmodulin-activated protein kinase, a NRGN downstream molecule. After developmental PTU exposure, the number of activity-regulated cytoskeleton-associated protein+ granule cells was also profoundly decreased in the ventral DG in parallel with the decrease in NRGN+ cells on PND 21. These results suggest that NRGN is a potential marker for suppression of synaptic plasticity in mature granule cells in the ventral DG.


Assuntos
Metilação de DNA , Efeitos Tardios da Exposição Pré-Natal , Feminino , Humanos , Animais , Ratos , Neurogranina/genética , Neurogranina/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Hipocampo , Proteínas/metabolismo , Neurogênese , Epigênese Genética , Etanol/metabolismo , Giro Denteado
6.
Neurotox Res ; 40(6): 2203-2220, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36098941

RESUMO

Lead (Pb) causes developmental neurotoxicity. Developmental exposure to Pb acetate (PbAc) induces aberrant hippocampal neurogenesis by increasing or decreasing neural progenitor cell (NPC) subpopulations in the dentate gyrus (DG) of rats. To investigate whether hippocampal neurogenesis is similarly affected by PbAc exposure in a general toxicity study, 5-week-old Sprague-Dawley rats were orally administered PbAc at 0, 4000, and 8000 ppm (w/v) in drinking water for 28 days. After exposure to 4000 or 8000 ppm PbAc, Pb had accumulated in the brains. Neurogenesis was suppressed by 8000 ppm PbAc, which was related to decreased number of type-2b NPCs, although number of mature granule cells were increased by both PbAc doses. Gene expression in the 8000 ppm PbAc group suggested suppressed NPC proliferation and increased apoptosis resulting in suppressed neurogenesis. PbAc exposure increased numbers of metallothionein-I/II+ cells and GFAP+ astrocytes in the DG hilus, and upregulated Mt1, antioxidant genes (Hmox1 and Gsta5), and Il6 in the DG, suggesting the induction of oxidative stress and neuroinflammation related to Pb accumulation resulting in suppressed neurogenesis. PbAc at 8000 ppm also upregulated Ntrk2 and increased the number of CALB2+ interneurons, suggesting the activation of BDNF-TrkB signaling and CALB2+ interneuron-mediated signals to ameliorate suppressed neurogenesis resulting in increased number of newborn granule cells. PbAc at both doses increased the number of ARC+ granule cells, suggesting the facilitation of synaptic plasticity of newborn granule cells through the activation of BDNF-TrkB signaling. These results suggest that PbAc exposure during the young-adult stage disrupted hippocampal neurogenesis, which had a different pattern from developmental exposure to PbAc. However, the induction of oxidative stress/neuroinflammation and activation of identical cellular signals occurred irrespective of the life stage at PbAc exposure.


Assuntos
Células-Tronco Neurais , Efeitos Tardios da Exposição Pré-Natal , Ratos , Animais , Feminino , Humanos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Chumbo , Doenças Neuroinflamatórias , Ratos Sprague-Dawley , Apoptose , Hipocampo/metabolismo , Neurogênese/fisiologia , Giro Denteado , Células-Tronco Neurais/metabolismo , Plasticidade Neuronal , Efeitos Tardios da Exposição Pré-Natal/metabolismo
7.
J Biol Chem ; 285(14): 10563-71, 2010 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-20124406

RESUMO

The soluble form of the chemokine fractalkine/CX(3)CL1 regulates microglia activation in the central nervous system (CNS), ultimately affecting neuronal survival. This study aims to determine whether CXCL12, another chemokine constitutively expressed in the CNS (known as stromal cell-derived factor 1; SDF-1), regulates cleavage of fractalkine from neurons. To this end, ELISA was used to measure protein levels of soluble fractalkine in the medium of rat neuronal cultures exposed to SDF-1. Gene arrays, quantitative RT-PCR, and Western blot were used to measure overall fractalkine expression in neurons. The data show that the rate of fractalkine shedding in healthy cultures positively correlates with in vitro differentiation and survival. In analogy to non-neuronal cells, metalloproteinases (ADAM10/17) are involved in cleavage of neuronal fractalkine as indicated by studies with pharmacologic inhibitors. Moreover, treatment of the neuronal cultures with SDF-1 stimulates expression of the inducible metalloproteinase ADAM17 and increases soluble fractalkine content in culture medium. The effect of SDF-1 is blocked by an inhibitor of both ADAM10 and -17, but only partially affected by a more specific inhibitor of ADAM10. In addition, SDF-1 also up-regulates expression of the fractalkine gene. Conversely, exposure of neurons to an excitotoxic stimulus (i.e. NMDA) inhibits alpha-secretase activity and markedly diminishes soluble fractalkine levels, leading to cell death. These results, along with previous findings on the neuroprotective role of both SDF-1 and fractalkine, suggest that this novel interaction between the two chemokines may contribute to in vivo regulation of neuronal survival by modulating microglial neurotoxic properties.


Assuntos
Córtex Cerebral/metabolismo , Quimiocina CX3CL1/metabolismo , Quimiocina CXCL12/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Proteínas ADAM/antagonistas & inibidores , Proteínas ADAM/metabolismo , Proteína ADAM10 , Proteína ADAM17 , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Western Blotting , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Quimiocina CX3CL1/genética , Quimiocina CXCL12/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Ensaio de Imunoadsorção Enzimática , Homeostase , N-Metilaspartato/farmacologia , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
J Comp Pathol ; 187: 2-6, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34503651

RESUMO

A 10-year-old spayed female Border Collie developed a ductal adenocarcinoma in the spleen. Clinically, the spleen was enlarged and a small liver nodule was present but there were no other abnormalities. Most of the splenic parenchyma was diffusely infiltrated by variably shaped atypical neoplastic cells that formed small clusters or larger nests, arranged as duct or duct-like structures within a fibrous matrix. There was acinar differentiation in a few portions of the tumour with a sheet-like solid growth pattern and occasional squamous metaplasia or exocrine acinus-like structures. Mitotic figures were frequent. Neoplastic cells with ductal differentiation were diffusely immunoreactive for AE1/AE3, CAM5.2 and CK7 cytokeratins but negative for CK20, while cells with acinar differentiation were immunolabelled only for AE1/AE3 cytokeratins and were also immunopositive for mucin-1 and trypsin. A few regions of tumour with ductal or acinar differentiation were immunopositive for pancreatic lipase. All neoplastic cells were negative for mucin-2, vimentin, smooth muscle actin, chromogranin A, CD31, hepatocyte paraffin 1 and thyroglobulin antigens. Because of the formation of exocrine acinus-like structures and an immunolabelling pattern consistent with exocrine pancreas tissue, an adenocarcinoma of ectopic exocrine pancreas within the spleen was diagnosed.


Assuntos
Adenocarcinoma , Doenças do Cão , Neoplasias Pancreáticas , Adenocarcinoma/veterinária , Animais , Cães , Feminino , Metaplasia/veterinária , Pâncreas Exócrino , Neoplasias Pancreáticas/veterinária
9.
Toxicol Lett ; 349: 69-83, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126181

RESUMO

Exposure to sterigmatocystin (STC) raises concerns on developmental neurological disorders. The present study investigated the effects of maternal oral STC exposure on postnatal hippocampal neurogenesis of offspring in rats. Dams were exposed to STC (1.7, 5.0, and 15.0 ppm in diet) from gestational day 6 until day 21 post-delivery (weaning), and offspring were maintained without STC exposure until adulthood on postnatal day (PND) 77, in accordance with OECD chemical testing guideline Test No. 426. On PND 21, 15.0-ppm STC decreased type-3 neural progenitor cell numbers in the subgranular zone (SGZ) due to suppressed proliferation. Increased γ-H2AX-immunoreactive (+) cell numbers in the SGZ and Ercc1 upregulation and Brip1 downregulation in the dentate gyrus suggested induction of DNA double-strand breaks in SGZ cells. Upregulation of Apex1 and Ogg1 and downregulation of antioxidant genes downstream of NRF2-Keap1 signaling suggested induction of oxidative DNA damage. Increased p21WAF1/CIP1+ SGZ cell numbers and suppressed cholinergic signaling through CHRNB2-containing receptors in GABAergic interneurons suggested potential neurogenesis suppression mechanisms. Multiple mechanisms involving N-methyl-d-aspartate (NMDA) receptor-mediated glutamatergic signaling and various GABAergic interneuron subpopulations, including CHRNA7-expressing somatostatin+ interneurons activated by BDNF-TrkB signaling, may be involved in ameliorating the neurogenesis. Upregulation of Arc, Ptgs2, and genes encoding NMDA receptors and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors suggested synaptic plasticity facilitation. On PND 77, ARC+ granule cells decreased, and Nos2 was upregulated following 15.0 ppm STC exposure, suggesting oxidative stress-mediated synaptic plasticity suppression. Inverse pattern in gene expression changes in vesicular glutamate transporter isoforms, Slc17a7 and Slc17a6, from weaning might also be responsible for the synaptic plasticity suppression. The no-observed-adverse-effect level of maternal oral STC exposure for offspring neurogenesis was determined to be 5.0 ppm, translating to 0.34-0.85 mg/kg body weight/day.


Assuntos
Proliferação de Células/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Esterigmatocistina/toxicidade , Animais , Apoptose/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla , Giro Denteado/metabolismo , Giro Denteado/patologia , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Nível de Efeito Adverso não Observado , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores de Neurotransmissores/genética , Receptores de Neurotransmissores/metabolismo , Desmame
10.
J Vet Diagn Invest ; 33(6): 1137-1141, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34672844

RESUMO

Neuroleptospirosis is a rare disease caused by pathogenic Leptospira interrogans in humans; however, it has not been fully studied in animals. A young wild raccoon dog was found convulsing in the recumbent position and died the next day. Histologic examination revealed nonsuppurative meningoencephalitis in the cerebrum, cerebellum, midbrain, and medulla oblongata. The lesions consisted of mixed infiltrates of Iba1-positive macrophages and CD3-positive T cells, with a small number of CD79α-positive B cells and myeloperoxidase-positive neutrophils. In the frontal cortex, perivascular cuffs and adjacent microglial nodules were distributed diffusely, especially in the molecular layer. Glial nodules were comprised of Iba1- and myeloperoxidase-positive activated microglia. Immunohistochemistry revealed leptospires in mononuclear cell perivascular cuffs, but not in glial nodules. Neuroleptospirosis was accompanied by Leptospira-related nonsuppurative interstitial nephritis, pulmonary edema and hemorrhage, and coronary periarteritis, as well as Toxocara tanuki in the small intestine and nonspecific foreign-body granulomas in the lungs and stomach.


Assuntos
Leptospira , Meningoencefalite , Animais , Imuno-Histoquímica , Meningoencefalite/veterinária , Cães Guaxinins , Toxocara
11.
J Neurosci ; 29(8): 2534-44, 2009 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-19244528

RESUMO

This study focuses on the effect of mu-opioid receptor agonists on CXCR4 signaling in neurons and the mechanisms involved in regulation of neuronal CXCR4 by opiates. The data show that CXCR4 is negatively modulated by long-term morphine treatments both in vitro and in vivo; CXCR4 inhibition is caused by direct stimulation of mu-opioid receptors in neurons, leading to alterations of ligand-induced CXCR4 phosphorylation and upregulation of protein ferritin heavy chain (FHC), a negative intracellular regulator of CXCR4. Reduced coupling of CXCR4 to G-proteins was found in the brain of morphine-treated rats, primarily cortex and hippocampus. CXCR4-induced G alpha(i)/G betagamma activities were suppressed after 24 h treatment of cortical neurons with morphine or the selective mu-opioid agonist DAMGO (D-Ala2-N-Me-Phe(4)-glycol(5)-enkephalin), as shown by analysis of downstream targets of CXCR4 (i.e., cAMP, Akt, and ERK1/2). These agonists also prevented CXCL12-induced phosphorylation of CXCR4, indicating a deficit of CXCR4 activation in these conditions. Indeed, morphine (or DAMGO) inhibited prosurvival signaling in neurons. These effects are not attributable to a reduction in CXCR4 expression or surface levels but rather to upregulation of FHC by opioids. The crucial role of FHC in inhibition of neuronal CXCR4 was confirmed by in vitro and in vivo RNA interference studies. Overall, these findings suggest that opiates interfere with normal CXCR4 function in the brain. By this mechanism, opiates could reduce the neuroprotective functions of CXCR4 and exacerbate neuropathology in opiate abusers who are affected by neuroinflammatory/infectious disorders, including neuroAIDS.


Assuntos
Apoferritinas/metabolismo , Encéfalo/efeitos dos fármacos , Morfina/farmacologia , Entorpecentes/farmacologia , Neurônios/efeitos dos fármacos , Receptores CXCR4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Análise de Variância , Animais , Apoferritinas/genética , Benzilaminas , Encéfalo/citologia , Quimiocina CXCL12/farmacologia , Ciclamos , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Compostos Heterocíclicos/farmacologia , Inibição Neural/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ratos , Receptores CXCR4/antagonistas & inibidores , Fatores de Tempo
12.
J Leukoc Biol ; 82(1): 44-56, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17442856

RESUMO

Human T cell leukemia virus type 1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is characterized by the generation of an intense CTL cell response directed against the viral transactivator protein Tax. In addition, patients diagnosed with HAM/TSP exhibit rapid activation and maturation of dendritic cells (DC), likely contributing to the robust, Tax-specific CTL response. In this study, extracellular Tax has been shown to induce maturation and functional alterations in human monocyte-derived DC, critical observations being confirmed in freshly isolated myeloid DC. Tax was shown to promote the production of proinflammatory cytokines and chemokines involved in the DC activation process in a dose- and time-dependent manner. Furthermore, Tax induced the expression of DC activation (CD40, CD80, and CD86) and maturation (CD83) markers and enhanced the T cell proliferation capability of DC. Heat inactivation of Tax resulted in abrogation of these effects, indicating a requirement for the native structure of Tax, which was found to bind efficiently to the DC membrane and was internalized within a few hours, suggesting that extracellular Tax may possess an intracellular mechanism of action subsequent to entry. Finally, inhibitors of cellular signaling pathways, NF-kappaB, protein kinase, tyrosine kinase, and phospholipase C, were shown to inhibit Tax-mediated DC activation. This is the first study reporting the immunomodulatory effects of extracellular Tax in the DC compartment. These results suggest that DC, once exposed to Tax by uptake from the extracellular environment, can undergo activation, providing constant antigen presentation and costimulation to T cells, leading to the intense T cell proliferation and inflammatory responses underlying HAM/TSP.


Assuntos
Células Dendríticas/imunologia , Produtos do Gene tax/farmacologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Apresentação de Antígeno , Comunicação Celular/imunologia , Citocinas/biossíntese , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/virologia , Infecções por HTLV-I/complicações , Infecções por HTLV-I/virologia , Humanos , Ativação Linfocitária/imunologia , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/virologia , Transdução de Sinais/efeitos dos fármacos , Doenças da Medula Espinal/imunologia , Doenças da Medula Espinal/virologia , Linfócitos T/imunologia
13.
J Pharm Sci ; 106(9): 2650-2656, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28411043

RESUMO

It was reported that stimulation of taste receptor type 2 member 38 by a bitter substance, phenylthiocarbamide (PTC), increased P-glycoprotein (P-gp) mRNA level and transport activity via release of the gastrointestinal hormone cholecystokinin-8 (CCK-8) at 9 h. Therefore, we hypothesized that CCK-8 and PTC might also regulate P-gp activity more rapidly via a different mechanism. As a result, we found that the pretreatment of human colon adenocarcinoma (Caco-2) cells with 10-mM PTC significantly decreased the intracellular accumulation of P-gp substrate rhodamine 123 (Rho123) compared with the control after 90-min incubation. Moreover, CCK-8 treatments significantly reduced the accumulation of Rho123 within 30 min, compared with the control. On the other hand, when Caco-2 cells were pretreated with PTC, the efflux ratio of Rho123 was significantly increased compared with control. The efflux ratio of Rho123 in CCK-8 treatment cells was also significantly increased compared with control. Furthermore, CCK-8 increased the phosphorylation of the scaffold proteins ezrin, radixin, and moesin, which regulate translocation of P-gp to the plasma membrane. Therefore, our results indicate that PTC induced release of CCK-8, which in turn induced the phosphorylation of ezrin, radixin, and moesin proteins, leading to upregulation of P-gp transport activity via increased membrane localization of P-gp.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Colecistocinina/metabolismo , Glicoproteínas de Membrana/metabolismo , Fragmentos de Peptídeos/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Western Blotting/métodos , Células CACO-2 , Técnicas de Cultura de Células , Membrana Celular , Colecistocinina/química , Proteínas do Citoesqueleto/metabolismo , Expressão Gênica , Humanos , Absorção Intestinal , Glicoproteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Fragmentos de Peptídeos/química , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , Rodamina 123/química , Rodamina 123/metabolismo , Transdução de Sinais/fisiologia
14.
J Neuropathol Exp Neurol ; 62(8): 801-11, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14503636

RESUMO

During the past decade, there has been accumulating evidence of the involvement of passive and active cell death mechanisms in both the clinical setting and in experimental models of traumatic brain injury (TBI). Traditionally, research for a treatment of TBI consists of strategies to prevent cell death using acute pharmacological therapy. However, to date, encouraging experimental work has not been translated into successful clinical trials. The development of cell replacement therapies may offer an alternative or a complementary strategy for the treatment of TBI. Recent experimental studies have identified a variety of candidate cell lines for transplantation into the injured CNS. Additionally, the characterization of the neurogenic potential of specific regions of the adult mammalian brain and the elucidation of the molecular controls underlying regeneration may allow for the development of neuronal replacement therapies that do not require transplantation of exogenous cells. These novel strategies may represent a new opportunity of great interest for delayed intervention in patients with TBI.


Assuntos
Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/terapia , Morte Celular , Regeneração Nervosa , Animais , Modelos Animais de Doenças , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Coloração e Rotulagem/métodos , Transplante/métodos
15.
Intern Med ; 43(8): 685-92, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15468966

RESUMO

OBJECTIVE: To quantitatively evaluate motor activity, its fluctuations, and drug effects in patients with Parkinson's disease (PD), the Lifecorder, a new monitoring device, was attached to a group of patients for several weeks. This enabled the continuous recording of motor activity in ten scaled magnitudes at two-minute intervals for 6 weeks. PATIENTS AND METHODS: Thirteen patients with PD who required dopamine receptor agonist therapy were monitored with Lifecorder, and seven healthy subjects served as the control group. The data obtained with this device correlated well with the Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn-Yahr grading. The dose of cabergoline, a D2-receptor agonist, was increased every 2 weeks, until optimum improvement was achieved. RESULTS: By adding cabergoline, the mean UPDRS improved from 40.5 to 28.4, which was significant. In parallel, the mean daily walking count (WC) also increased from 2,459 to 3,315 steps (p < 0.01) and movement-related calorie consumption (MCC) increased from 56 to 74 kcal (p < 0.05). UPDRS thus correlated well with WC and MCC (p < 0.05) obtained with this device. The improvement ratio of WC and MCC of each individual patient was compared with that of UPDRS. WC, and MCC shifted in parallel with UPDRS with one exception. The daily time-dependent fluctuation of motor activity was clearly shown by the Excel-generated graphs to improve with D-agonist therapy. In contrast to enhanced daytime activities, nocturnal restfulness was also clearly documented with this device. CONCLUSION: The unique properties of Lifecorder make this device a useful adjunct to the UPDRS for the objective evaluation of Parkinsonian motor activity. The device has a significant advantage over conventional clinical scales, as daytime as well as nocturnal motor activity can be objectively evaluated over long time periods ranging from one hour to one month, and the magnitude of motor activity is quantifiable in relation to the time-course.


Assuntos
Monitorização Ambulatorial/instrumentação , Atividade Motora/fisiologia , Doença de Parkinson/fisiopatologia , Idoso , Antiparkinsonianos/uso terapêutico , Cabergolina , Ritmo Circadiano , Agonistas de Dopamina/uso terapêutico , Ergolinas/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico
16.
Methods Mol Biol ; 1013: 31-48, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23625491

RESUMO

Quantifying protein and RNA expression within specific cell populations in vivo is an essential step in unraveling the complex mechanisms of neurological disease. The challenges associated with studying human brain tissue are commonly compounded by variations in postmortem interval, formalin fixation time, and tissue processing methods among others. The result is a sample population that is inherently heterogeneous, implying the need for reliable protocols that are sensitive to low levels of antigen while minimizing background and nonspecific staining. Here, we describe a single immunohistochemistry protocol on formalin-fixed, paraffin-embedded human cortex which can be adapted to (1) quantify the relative protein expression of the chemokine receptor, CXCR4, using multispectral image or (2) isolate neuronal RNA through automated laser capture microdissection.


Assuntos
Córtex Cerebral/química , Imuno-Histoquímica , Microdissecção e Captura a Laser , Microscopia , Neurônios/química , Receptores CXCR4/análise , Automação Laboratorial , Córtex Cerebral/citologia , Fixadores , Formaldeído , Humanos , Processamento de Imagem Assistida por Computador , Inclusão em Parafina , RNA/isolamento & purificação , Receptores CXCR4/genética , Fixação de Tecidos
17.
Anal Cell Pathol (Amst) ; 35(2): 107-15, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22002723

RESUMO

In the field of whole slide imaging, the imaging device or staining process cause color variations for each slide that affect the result of image analysis made by pathologist. In order to stabilize the analysis, we developed a color standardization method and system as described below. (1) Color standardization method based on RGB imaging and multi spectral sensing, which utilize less band (16 bands) than conventional method (60 bands). (2) High speed spectral sensing module. As a result, we confirmed the following effect. (1) We confirmed the performance improvement of nucleus detection by the color standardization. And we can conduct without training data set which is needed in conventional method. (2) We can get detection performance of H&E component equivalent to conventional method (60 bands). And measurement process is more than 255 times faster.


Assuntos
Interpretação de Imagem Assistida por Computador/normas , Análise Espectral/normas , Algoritmos , Cor , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Padrões de Referência , Análise Espectral/métodos , Coloração e Rotulagem
18.
J Vis Exp ; (57)2011 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-22105098

RESUMO

This video will guide you through the process of culturing rat cortical neurons in the presence of a glial feeder layer, a system known as a bilaminar or co-culture model. This system is suitable for a variety of experimental needs requiring either a glass or plastic growth substrate and can also be used for culture of other types of neurons. Rat cortical neurons obtained from the late embryonic stage (E17) are plated on glass coverslips or tissue culture dishes facing a feeder layer of glia grown on dishes or plastic coverslips (known as Thermanox), respectively. The choice between the two configurations depends on the specific experimental technique used, which may require, or not, that neurons are grown on glass (e.g. calcium imaging versus Western blot). The glial feeder layer, an astroglia-enriched secondary culture of mixed glia, is separately prepared from the cortices of newborn rat pups (P2-4) prior to the neuronal dissection. A major advantage of this culture system as compared to a culture of neurons only is the support of neuronal growth, survival, and differentiation provided by trophic factors secreted from the glial feeder layer, which more accurately resembles the brain environment in vivo. Furthermore, the co-culture can be used to study neuronal-glial interactions(1). At the same time, glia contamination in the neuronal layer is prevented by different means (low density culture, addition of mitotic inhibitors, lack of serum and use of optimized culture medium) leading to a virtually pure neuronal layer, comparable to other established methods(1-3). Neurons can be easily separated from the glial layer at any time during culture and used for different experimental applications ranging from electrophysiology(4), cellular and molecular biology(5-8), biochemistry(5), imaging and microscopy(4,6,7,9,10). The primary neurons extend axons and dendrites to form functional synapses(11), a process which is not observed in neuronal cell lines, although some cell lines do extend processes. A detailed protocol of culturing rat hippocampal neurons using this co-culture system has been described previously(4,12,13). Here we detail a modified protocol suited for cortical neurons. As approximately 20x10(6) cells are recovered from each rat embryo, this method is particularly useful for experiments requiring large numbers of neurons (but not concerned about a highly homogenous neuronal population). The preparation of neurons and glia needs to be planned in a time-specific manner. We will provide the step-by-step protocol for culturing rat cortical neurons as well as culturing glial cells to support the neurons.


Assuntos
Córtex Cerebral/citologia , Técnicas Citológicas/métodos , Neuroglia/citologia , Neurônios/citologia , Animais , Técnicas de Cocultura , Dissecação , Ratos
19.
PLoS One ; 6(5): e20680, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21655198

RESUMO

BACKGROUND: CXCR7 and CXCR4 are receptors for the chemokine CXCL12, which is involved in essential functions of the immune and nervous systems. Although CXCR7 transcripts are widely expressed throughout the central nervous system, little is known about its protein distribution and function in the adult brain. To evaluate its potential involvement in CXCL12/CXCR4 signaling in differentiated neurons, we studied CXCR7 protein expression in human brain and cultured neurons. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistochemistry and RT-PCR analyses of cortex and hippocampus from control and HIV-positive subjects provided the first evidence of CXCR7 protein expression in human adult neurons, under normal and pathological conditions. Furthermore, confocal microscopy and binding assays in cultured neurons show that CXCR7 protein is mainly located into cytoplasm, while little to no protein expression is found on neuronal plasma membrane. Interestingly, specific CXCR7 ligands that inhibit CXCL12 binding to CXCR7 do not alter CXCR4-activated survival signaling (pERK/pAkt) in rat cortical neurons. Neuronal CXCR7 co-localizes to some extent with the endoplasmic reticulum marker ERp29, but not with early/late endosome markers. Additionally, large areas of overlap are detected in the intracellular pattern of CXCR7 and CXCR4 expression. CONCLUSIONS/SIGNIFICANCE: Overall, these results implicate CXCR4 as the main CXCL12 signaling receptor on the surface of differentiated neurons and suggest that CXCR7 may interact with CXCR4 at the intracellular level, possibly affecting CXCR4 trafficking and/or coupling to other proteins.


Assuntos
Neurônios/citologia , Neurônios/metabolismo , Receptores CXCR/metabolismo , Adulto , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Receptores CXCR/genética , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Neuroimmunol ; 224(1-2): 66-71, 2010 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-20627326

RESUMO

The chemokine CXCL12 and its receptor, CXCR4, regulate neuronal migration, differentiation, and survival. Alterations of CXCL12/CXCR4 signaling are implicated in different neuropathologies, including the neurological complications of HIV infection. Opiates are important co-factors for progression to neuroAIDS and can disrupt the CXCL12/CXCR4 axis in vitro and in vivo. This paper will review recently identified mechanisms of opiate-induced CXCR4 impairment in neurons and introduce results from pilot studies in human brain tissue, which highlight the role of the protein ferritin heavy chain in HIV neuropathology in patients with history of drug abuse.


Assuntos
Complexo AIDS Demência/etiologia , Complexo AIDS Demência/imunologia , Apoferritinas/efeitos adversos , Neurônios/imunologia , Neurônios/patologia , Transtornos Relacionados ao Uso de Opioides/imunologia , Transtornos Relacionados ao Uso de Opioides/metabolismo , Receptores CXCR4/metabolismo , Complexo AIDS Demência/patologia , Animais , Apoferritinas/fisiologia , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/fisiologia , Comorbidade , Humanos , Neurônios/metabolismo , Transtornos Relacionados ao Uso de Opioides/patologia , Receptores CXCR4/fisiologia
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