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1.
Int J Mol Sci ; 25(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38892462

RESUMO

For patients with hereditary breast and ovarian cancer, the probability of carrying two pathogenic variants (PVs) in dominant cancer-predisposing genes is rare. Using targeted next-generation sequencing (NGS), we investigated a 49-year-old Caucasian woman who developed a highly aggressive breast tumor. Our analyses identified an intragenic germline heterozygous duplication in BRCA1 with an additional likely PV in the TP53 gene. The BRCA1 variant was confirmed by multiplex ligation probe amplification (MLPA), and genomic breakpoints were characterized at the nucleotide level (c.135-2578_442-1104dup). mRNA extracted from lymphocytes was amplified by RT-PCR and then Sanger sequenced, revealing a tandem duplication r.135_441dup; p.(Gln148Ilefs*20). This duplication results in the synthesis of a truncated and, most likely, nonfunctional protein. Following functional studies, the TP53 exon 5 c.472C > T; p.(Arg158Cys) missense variant was classified as likely pathogenic by the Li-Fraumeni Syndrome (LFS) working group. This type of unexpected association will be increasingly identified in the future, with the switch from targeted BRCA sequencing to hereditary breast and ovarian cancer (HBOC) panel sequencing, raising the question of how these patients should be managed. It is therefore important to record and investigate these rare double-heterozygous genotypes.


Assuntos
Proteína BRCA1 , Neoplasias de Mama Triplo Negativas , Proteína Supressora de Tumor p53 , Humanos , Feminino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética , Proteína BRCA1/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Duplicação Gênica , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Sequenciamento de Nucleotídeos em Larga Escala
2.
J Zoo Wildl Med ; 52(1): 192-199, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33827176

RESUMO

Enterotoxemia is an important issue in various zoological taxa. In this study, serologic responses over a 1-yr period after vaccination with a multivalent clostridial vaccine were evaluated in 10 adult springboks (Antidorcas marsupialis), 12 impalas (Aepyceros melampus), seven alpacas (Vicugna pacos), and five red-necked wallabies (Macropus rufogriseus). Antibody production to the Clostridium perfringens type D epsilon toxin component of the vaccine was measured using an indirect enzyme-linked immunosorbent assay and determined as the percentage of inhibition (% inhib). Initial % inhib was (0.01-18.9)%. All animals received initial vaccination with a booster vaccine 4 weeks apart. Serum samples were collected at T0 (nonvaccinated), 15, 30, 60, 180, and 360 days postvaccination (dpv) for analysis. The vaccine induced a high antibody response that peaked at 15, 30, and 60 dpv in springboks, 30 and 60 dpv in impalas (P < 0.01), and 60 dpv in alpacas and wallabies (P < 0.01). The booster vaccine was followed by a high antibody response, which slowly decreased with time. The antibody response was significantly higher at 360 dpv than at T0 in wallabies and alpacas (P < 0.01). In impalas and springboks, it appeared that a booster every 6 mo might be required to maintain an antibody response above baseline (P < 0.01). Because no challenge studies were performed, it is unknown whether the measured humoral immune responses would have been protective. Further research is warranted to investigate protective effects of antibodies to inoculation challenge in nondomestic species.


Assuntos
Antílopes/sangue , Toxinas Bacterianas/imunologia , Vacinas Bacterianas/imunologia , Camelídeos Americanos/sangue , Clostridium perfringens/imunologia , Macropodidae/sangue , Animais , Animais de Zoológico , Antílopes/imunologia , Anticorpos Antibacterianos/sangue , Camelídeos Americanos/imunologia , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Feminino , Macropodidae/imunologia , Masculino , Fatores de Tempo
3.
Dis Aquat Organ ; 142: 119-124, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33269723

RESUMO

An outbreak of salmonellosis occurred in a group of 7 long-nosed fur seals Arctocephalus forsteri undergoing rehabilitation after being found injured and malnourished on beaches along the northern New South Wales and southern Queensland coasts of Australia. Three of the 7 individuals developed clinical disease and died within 3 d. Clinical signs included profuse diarrhea, vomiting, depression, and lethargy. Salmonella enterica subsp. enterica serovar Kentucky (S. Kentucky) was cultured from 2 of the 3 deceased animals. The other 4 animals showed similar signs and recovered following treatment. S. Kentucky (antigenic formula 8,20:i:z6) was isolated from the survivors and tissues recovered from post-mortem samples of deceased animals. The bacterium was susceptible to cephalothin and sulfamethoxazole/trimethoprim and resistant to amoxicillin-clavulanate, ampicillin/amoxicillin, tetracycline, and enrofloxacin. This organism has the potential to cause disease in aquatic wildlife, as well as posing a zoonotic threat to people who utilise the aquatic environment.


Assuntos
Otárias , Animais , Antibacterianos/farmacologia , Austrália , Surtos de Doenças/veterinária , Farmacorresistência Bacteriana Múltipla , Kentucky/epidemiologia , Testes de Sensibilidade Microbiana/veterinária , New South Wales , Queensland , Salmonella
4.
J Fish Dis ; 41(9): 1453-1458, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29882594

RESUMO

This report describes a case of systemic bacterial infection caused by Edwardsiella tarda in a Western African lungfish (Protopterus annectens) exposed to poor environmental and husbandry conditions. The fish presented with a large, external ulcerative lesion and died 2 weeks after developing anorexia. Histological evaluation revealed multifocal areas of necrosis and heterophilic and histiocytic inflammation throughout multiple tissues. Gram stain identified small numbers of intra- and extracellular monomorphic Gram-negative 1 to 2 µm rod-shaped bacilli. Cytology of lung granuloma, kidney and testes imprints identified heterophilic inflammation with phagocytosis of small monomorphic bacilli and some heterophils exhibiting cytoplasmic projections indicative of heterophil extracellular traps (HETs). Initial phenotypic analysis of isolates from coelomic fluid cultures identified E. tarda. Subsequent molecular analysis of spleen, liver and intestine DNA using an E. tarda-specific endpoint PCR assay targeting the bacterial fimbrial subunit yielded a 115 bp band. Sequencing and BLASTN search revealed the sequence was identical (76/76) to E. tarda strain FL95-01 (GenBank acc. CP011359) and displayed 93% sequence identity (66/71) to Edwardsiella hoshinae strain ATCC 35051 (GenBank acc. CP011359). This is the first report of systemic edwardsiellosis in a lungfish with concurrent cytologically identified structures suggestive of HETs.


Assuntos
Edwardsiella tarda/isolamento & purificação , Infecções por Enterobacteriaceae/veterinária , Doenças dos Peixes/sangue , Peixes/microbiologia , Animais , Anorexia , Técnicas Citológicas , DNA Bacteriano/genética , Edwardsiella tarda/genética , Edwardsiella tarda/imunologia , Edwardsiella tarda/fisiologia , Infecções por Enterobacteriaceae/sangue , Infecções por Enterobacteriaceae/microbiologia , Armadilhas Extracelulares/imunologia , Doenças dos Peixes/microbiologia , Granulócitos/ultraestrutura , Rim/citologia , Rim/microbiologia , Rim/patologia , Pulmão/citologia , Pulmão/microbiologia , Pulmão/patologia , Pulmão/ultraestrutura , Masculino , Filogenia , Reação em Cadeia da Polimerase , Sepse/microbiologia , Testículo/citologia , Testículo/microbiologia , Testículo/patologia
5.
J Toxicol Environ Health A ; 80(10-12): 556-561, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28841368

RESUMO

Threatened loggerhead sea turtles (Caretta caretta) face numerous environmental challenges, including exposure to anthropogenic chemicals such as polychlorinated biphenyls (PCBs). Despite being banned by the USA in the 1970s, PCBs persist in the environment and produce immunotoxic effects in a wide range of marine vertebrate species. This is of particular concern, as the modulation of the immune system may enhance the susceptibility to a variety of pathogens. Blood samples were collected from 19 immature, captive-reared loggerhead sea turtles. Functional immune assays phagocytosis and natural killer (NK) cell activity were used to quantify the direct effects of PCB congeners 105, 138, and 169 on innate immune functions upon in vitro exposure of sea turtle cells to increasing concentrations (control (0), 0.5, 1, 2.5, 5, 10, 15, or 20 ppm) of each PCB. PCB 105 significantly elevated eosinophil phagocytosis at 10 and 15 ppm and PCB 138 at 15 ppm compared to unexposed (0 ppm). The effects of PCB 169 on phagocytosis were not evaluated. PCB 138 and 105 significantly decreased NK cell activity at 15 and 20 ppm, compared to unexposed (0 ppm) controls. PCB 169 did not markedly modulate NK activity. This constitutes the first study to investigate the in vitro effects of these three PCBs on sea turtle innate immune functions. These results add to our understanding of PCB-induced immunotoxicity in sea turtles and may provide a framework for establishing the relationships between chemical levels and turtle immunity.


Assuntos
Exposição Ambiental , Células Matadoras Naturais/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Tartarugas/fisiologia , Poluentes Químicos da Água/toxicidade , Animais
6.
Proc Natl Acad Sci U S A ; 110(43): 17362-7, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24101515

RESUMO

PC7 belongs to the proprotein convertase family, whose members are implicated in the cleavage of secretory precursors. The in vivo function of PC7 is unknown. Herein, we find that the precursor proBDNF is processed into mature BDNF in COS-1 cells coexpressing proBDNF with either PC7 or Furin. Conversely, the processing of proBDNF into BDNF is markedly reduced in the absence of either Furin or PC7 in mouse primary hepatocytes. In vivo we observe that BDNF and PC7 mRNAs are colocalized in mouse hippocampus and amygdala and that mature BDNF protein levels are reduced in these brain areas in PC7 KO mice but not in the hippocampus of PC1/3 KO mice. Various behavioral tests reveal that in PC7 KO mice spatial memory is intact and plasticity of responding is mildly abnormal. Episodic and emotional memories are severely impaired, but both are rescued with the tyrosine receptor kinase B agonist 7,8-dihydroxyflavone. Altogether, these results support an in vivo role for PC7 in the regulation of certain types of cognitive performance, in part via proBDNF processing. Because polymorphic variants of human PC7 are being characterized, it will be important in future studies to determine their effects on additional physiological and behavioral processes.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Subtilisinas/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Western Blotting , Células COS , Células Cultivadas , Chlorocebus aethiops , Feminino , Flavanonas/farmacologia , Expressão Gênica , Células HEK293 , Hepatócitos/citologia , Hepatócitos/metabolismo , Hipocampo/metabolismo , Humanos , Hibridização In Situ , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Camundongos , Camundongos Knockout , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Subtilisinas/genética
7.
Proc Natl Acad Sci U S A ; 107(7): 3081-6, 2010 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-20133765

RESUMO

Cholesterol metabolism has been implicated in the pathogenesis of several neurodegenerative diseases, including the abnormal accumulation of amyloid-beta, one of the pathological hallmarks of Alzheimer disease (AD). Acyl-CoA:cholesterol acyltransferases (ACAT1 and ACAT2) are two enzymes that convert free cholesterol to cholesteryl esters. ACAT inhibitors have recently emerged as promising drug candidates for AD therapy. However, how ACAT inhibitors act in the brain has so far remained unclear. Here we show that ACAT1 is the major functional isoenzyme in the mouse brain. ACAT1 gene ablation (A1-) in triple transgenic (i.e., 3XTg-AD) mice leads to more than 60% reduction in full-length human APPswe as well as its proteolytic fragments, and ameliorates cognitive deficits. At 4 months of age, A1- causes a 32% content increase in 24-hydroxycholesterol (24SOH), the major oxysterol in the brain. It also causes a 65% protein content decrease in HMG-CoA reductase (HMGR) and a 28% decrease in sterol synthesis rate in AD mouse brains. In hippocampal neurons, A1- causes an increase in the 24SOH synthesis rate; treating hippocampal neuronal cells with 24SOH causes rapid declines in hAPP and in HMGR protein levels. A model is provided to explain our findings: in neurons, A1- causes increases in cholesterol and 24SOH contents in the endoplasmic reticulum, which cause reductions in hAPP and HMGR protein contents and lead to amelioration of amyloid pathology. Our study supports the potential of ACAT1 as a therapeutic target for treating certain forms of AD.


Assuntos
Acetil-CoA C-Acetiltransferase/deficiência , Doença de Alzheimer/genética , Amiloide/metabolismo , Encéfalo/metabolismo , Hidroxicolesteróis/metabolismo , Modelos Biológicos , Acetil-CoA C-Acetiltransferase/genética , Acil Coenzima A/metabolismo , Doença de Alzheimer/enzimologia , Doença de Alzheimer/patologia , Animais , Colesterol/metabolismo , Inativação Gênica , Humanos , Camundongos , Camundongos Transgênicos
8.
J Zoo Wildl Med ; 44(4): 859-74, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24450044

RESUMO

Abstract: Blood samples of 85 immature, apparently healthy, captive-reared loggerhead sea turtles (Caretta caretta) were analyzed for 13 hematologic variables and total solids of 5 age groups (8, 20, 32, 44, and 56 mo old) and for 20 plasma biochemical analytes of 4 age groups (20 to 56 mo old). Each individual turtle was sampled under similar conditions during a blood collection period of 3 days. Hematologic analytes included packed cell volume, white blood cell (WBC) counts, WBC estimates, and leukocyte differentials. Biochemical analysis included albumin, alanine aminotransferase, alkaline phosphatase, amylase, aspartate aminotransferase, blood urea nitrogen, calcium, chloride, cholesterol, creatine kinase, creatinine, gamma glutamyltransferase, globulins, glucose, phosphorous, potassium, sodium, total bilirubin, total protein, total solids, and uric acid. In due consideration of small sample size in all five age groups, the results of hematologic and biochemical analysis were used to determine ranges for these analytes and to compare values among consecutive age groups. Several significant differences in some hematologic and biochemical variables were identified and need to be considered in the interpretation of blood work of immature, growing sea turtles in human care.


Assuntos
Contagem de Células Sanguíneas/veterinária , Análise Química do Sangue/veterinária , Testes Hematológicos/veterinária , Tartarugas/sangue , Animais , Valores de Referência
9.
Mol Pharmacol ; 82(5): 948-57, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22909796

RESUMO

Reactive astrogliosis is beneficial in many aspects; however, it is also detrimental in some pathological states such as the development of lethal brain tumors. It is therefore crucial to understand the mechanisms regulating astrocyte proliferation. Tumor necrosis factor-like weak inducer of apoptosis (TWEAK), a member of the tumor necrosis factor family, was shown to stimulate astrocyte proliferation in vitro. Herein, we further characterize the mitogenic potential of TWEAK on central nervous system cells. Among these cells, astrocytes express the highest level of TWEAK and Fn14 transcripts, suggesting that they are particularly sensitive to TWEAK stimulation. Using in vitro model systems, we found that TWEAK was as potent as epidermal growth factor (EGF) (a prototypical astrocyte mitogen) in mediating astrocyte proliferation. However, its mitogenic activity was delayed compared with that of EGF, suggesting distinct mechanisms of action. Using cell signaling pathway inhibitors, neutralizing antibodies, and protein assays, we further show that the mitogenic activity of TWEAK on primary astrocytes requires stimulation of the transforming growth factor-α (TGF-α) and of the epidermal growth factor receptor (EGFR) signaling pathway through extracellular signal-regulated kinase and p38 mitogen-activated protein kinase activation. In aggregates, our data demonstrate that TWEAK acts as a potent astrocyte mitogen through the induction of a TGF-α/EGFR signaling pathway. We anticipate that description of such a mechanism may allow novel approaches to human pathologies associated with astrocyte proliferation.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Astrócitos/citologia , Receptores ErbB/fisiologia , Proteínas de Membrana/metabolismo , Fator de Crescimento Transformador alfa/fisiologia , Fatores de Necrose Tumoral/metabolismo , Animais , Proteínas Reguladoras de Apoptose/farmacologia , Astrócitos/metabolismo , Proliferação de Células , Citocina TWEAK , Embrião de Mamíferos , Ativação Enzimática , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/antagonistas & inibidores , Proteínas de Membrana/farmacologia , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Cultura Primária de Células , Ratos , Ratos Wistar , Receptores do Fator de Necrose Tumoral/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Receptor de TWEAK , Fatores de Necrose Tumoral/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
J Biol Chem ; 286(4): 2728-38, 2011 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21075846

RESUMO

The zymogen activation mechanism and physiological functions of the most ancient and highly conserved basic amino acid-specific proprotein convertase 7 (PC7) are not known. Herein, we characterized the biosynthesis, subcellular localization, and trafficking of the membrane-bound full-length rat and human PC7. The prosegment of PC7 is primarily secreted alone as a non-inhibitory protein via the conventional, Golgi-dependent, secretory pathway. Mature PC7 is partially sulfated and thus reaches the cell surface via the conventional route. However, a fraction of PC7 reaches the cell surface through a brefeldin A- and COPII-independent unconventional secretory pathway. The latter trafficking may explain the rapid (<10 min) transit of a fraction of PC7 from the ER to the cell surface. Electron microscopy further confirmed the localization of PC7 to the cell surface of HEK293 cells. Within the cytosolic tail, only two cysteines (Cys(699) and Cys(704)) are palmitoylated, but this modification does not affect the choice of trafficking pathway. Swapping the transmembrane-cytosolic tail (TMCT) sequences of the convertases Furin and PC7 revealed that PC7(TMCT-Furin) is much more sulfated and hence traffics more efficiently through the conventional secretory pathway. In contrast, the Furin(TMCT-PC7) is no longer sulfated and thus reaches the cell surface by the unconventional pathway. Because trafficking of PC7(CT-Furin) and Furin(CT-PC7) resemble their wild type counterparts, we deduce that the transmembrane domain of PC7 regulates the sorting of PC7 toward the unconventional secretory pathway. In conclusion, PC7 is distinct from other proprotein convertases in its zymogen activation, subcellular localization, and trafficking.


Assuntos
Retículo Endoplasmático/enzimologia , Precursores Enzimáticos/metabolismo , Subtilisinas/metabolismo , Animais , Células COS , Chlorocebus aethiops , Ativação Enzimática/fisiologia , Precursores Enzimáticos/genética , Furina/genética , Furina/metabolismo , Células HEK293 , Humanos , Estrutura Terciária de Proteína , Transporte Proteico/fisiologia , Ratos , Subtilisinas/genética
11.
J Biol Chem ; 286(11): 9185-95, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21209099

RESUMO

Although the processing profile of the membrane-bound epidermal growth factor precursor (pro-EGF) is tissue-specific, it has not been investigated at the cellular level nor have the cognate proteinases been defined. Among the proprotein convertases (PCs), only the membrane-bound PC7, the most ancient and conserved basic amino acid-specific PC family member, induces the processing of pro-EGF into an ∼115-kDa transmembrane form (EGF-115) at an unusual VHPR(290)↓A motif. Because site-directed mutagenesis revealed that Arg(290) is not critical, the generation of EGF-115 by PC7 is likely indirect. This was confirmed by testing a wide range of protease inhibitors, which revealed that the production of EGF-115 is most probably achieved via the activation by PC7 of a latent serine and/or cysteine protease(s). EGF-115 is more abundant at the cell surface than pro-EGF and is associated with a stronger EGF receptor (EGFR) activation, as evidenced by higher levels of phosphorylated ERK1/2. This suggests that the generation of EGF-115 represents a regulatory mechanism of juxtacrine EGFR activation. Thus, PC7 is distinct from the other PCs in its ability to enhance the activation of the cell surface EGFR.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Subtilisinas/metabolismo , Animais , Células COS , Chlorocebus aethiops , Fator de Crescimento Epidérmico/genética , Receptores ErbB/genética , Células HEK293 , Humanos , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Inibidores de Proteases/farmacologia , Precursores de Proteínas/genética , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Subtilisinas/antagonistas & inibidores , Subtilisinas/genética
12.
J Neurochem ; 122(5): 1032-46, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22708926

RESUMO

1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication of mice is a standard model of Parkinson's disease (PD). However, it does not reproduce functionally PD. Given the occurrence of PD during aging, symptoms might only be detected in MPTP-intoxicated mice after aging. To address this, mice injected with MPTP at 2.5 months were followed up to a maximum age of 21 months. There was no loss of dopamine cells with aging in control mice; moreover, the initial post-MPTP intoxication decrease in dopamine cell was no longer significant at 21 months. With aging, striatal dopamine level remained constant, but concentrations of the dopamine metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were markedly reduced in both groups. There was also a late impairment of fine motor skills. After MPTP intoxication, hyperactivity was immediately detected and it became greater than in control mice from 14 months of age; fine motor skills were also more impaired; both these symptoms were correlated with striatal dopamine, DOPAC and HVA concentrations. In bothgroups, neither motor symptoms nor dopamine changes worsened with age. These findings do not support the notion that PD develops with age in mice after MPTP intoxication and that the motor deficits seen are because of an aging process.


Assuntos
Envelhecimento , Comportamento Animal/fisiologia , Encéfalo/patologia , Dopamina/metabolismo , Intoxicação por MPTP , Atividade Motora/fisiologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Fatores Etários , Envelhecimento/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Homovanílico/metabolismo , Intoxicação por MPTP/induzido quimicamente , Intoxicação por MPTP/patologia , Intoxicação por MPTP/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Neurotoxinas/farmacologia , Teste de Desempenho do Rota-Rod , Estatística como Assunto , Tirosina 3-Mono-Oxigenase/metabolismo
13.
J Lipid Res ; 52(7): 1383-91, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21518694

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a major role in cholesterol homeostasis through enhanced degradation of the LDL receptor (LDLR) in liver. As novel inhibitors/silencers of PCSK9 are now being tested in clinical trials to treat hypercholesterolemia, it is crucial to define the physiological consequences of the lack of PCSK9 in various organs. LDLR regulation by PCSK9 has not been extensively described during mouse brain development and injury. Herein, we show that PCSK9 and LDLR are co-expressed in mouse brain during development and at adulthood. Although the protein levels of LDLR and apolipoprotein E (apoE) in the adult brain of Pcsk9(-/-) mice are similar to those of wild-type (WT) mice, LDLR levels increased and were accompanied by a reduction of apoE levels during development. This suggests that the upregulation of LDLR protein levels in Pcsk9(-/-) mice enhances apoE degradation. Upon ischemic stroke, PCSK9 was expressed in the dentate gyrus between 24 h and 72 h following brain reperfusion. Although mouse behavior and lesion volume were similar, LDLR protein levels dropped ∼2-fold less in the Pcsk9(-/-)-lesioned hippocampus, without affecting apoE levels and neurogenesis. Thus, PCSK9 downregulates LDLR levels during brain development and following transient ischemic stroke in adult mice.


Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Receptores de LDL/metabolismo , Serina Endopeptidases/metabolismo , Animais , Apolipoproteínas E/metabolismo , Isquemia Encefálica/complicações , Isquemia Encefálica/genética , Cerebelo/metabolismo , Giro Denteado/metabolismo , Camundongos , Pró-Proteína Convertase 9 , Pró-Proteína Convertases , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Serina Endopeptidases/deficiência , Serina Endopeptidases/genética , Acidente Vascular Cerebral/complicações , Telencéfalo/metabolismo , Fatores de Tempo , Regulação para Cima
14.
Dev Dyn ; 239(11): 2933-46, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20882679

RESUMO

Pro-protein convertase subtilisin/kexin 5 (PC5, also known as PC6) is a member of the subtilisin-like superfamily of serine proteases implicated in the maturation of latent precursor proteins into their functionally active derivatives. To investigate the functional roles, we have cloned the cDNA sequences encoding two candidate zebrafish PC5 convertases (designated as PCSK5.1 and PCSK5.2) co-orthologous to the single PC5 encoding gene (PCSK5) found in mammals. Both display syntenic correspondence to the human PCSK5 gene. Overall gene architecture has been conserved across species. While PC5.1 mRNA expression is very discrete within the otic vesicle and lateral line neuromasts, PC5.2 transcripts are more ubiquitously expressed within the central nervous system together with specific localization in various organs including liver, intestine, and otic vesicle. Zebrafish PC5.1-deficient embryos display abnormal neuromast deposition within the lateral line system and lack a normal touch response, consistent with the known sensory role that the lateral line plays in spatial awareness and sensing the environment.


Assuntos
Pró-Proteína Convertase 5/química , Pró-Proteína Convertase 5/metabolismo , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Northern Blotting , Western Blotting , Embrião não Mamífero/metabolismo , Humanos , Hibridização In Situ , Camundongos , Dados de Sequência Molecular , Pró-Proteína Convertase 5/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
15.
J Wildl Dis ; 55(1): 258-261, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30235083

RESUMO

An adult male pygmy sperm whale ( Kogia breviceps) stranded alive at a beach in Florida, US, in 2016. Main postmortem examination findings included bilateral multifocal variably sized renal cysts, focal renal cystadenoma, and mild dilation of the renal pelvises. The role of these renal lesions in the stranding of this whale is unknown.


Assuntos
Cistadenoma/veterinária , Neoplasias Renais/veterinária , Doenças Renais Policísticas/veterinária , Baleias , Animais , Cistadenoma/patologia , Neoplasias Renais/patologia , Masculino , Doenças Renais Policísticas/patologia
16.
Ann Clin Transl Neurol ; 6(9): 1681-1695, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31400065

RESUMO

OBJECTIVES: Blood biomarkers for cerebral tissue ischemia are lacking. The goal was to identify a blood transcriptomic signature jointly identified in the ischemic brain. METHODS: A nonhuman primate model with middle cerebral artery (MCA) territory infarction was used to study gene expression by microarray during acute ischemic cerebral stroke in the brain and the blood. Brain samples were collected in the infarcted and contralateral non-infarcted cortex as well as blood samples before and after occlusion. Gene expression was compared between the two brain locations to find differentially expressed genes. The expressions of these genes were then compared in the blood pre- and post-occlusion. RESULTS: Hierarchical clustering of brain expression data revealed strong independent clustering of ischemic and nonischemic brain samples. The top five enriched, up-regulated gene sets in the brain were TNF α signaling, apoptosis, P53 pathway, hypoxia, and UV response up. A comparison of differentially expressed genes in the brain and blood revealed a significant overlap of gene expression patterns. Stringent analysis of blood expression data from pre- and post-occlusion samples in each monkey identified nine genes highly differentially expressed in both the brain and the blood. Many of these up-regulated genes belong to pathways involved in cell death and DNA damage repair. INTERPRETATION: Common gene expression profile can be identified in the brain and blood and clearly differentiates ischemic from nonischemic conditions. Therefore, specific blood transcriptomic signature may represent a surrogate for brain ischemic gene expression.


Assuntos
Isquemia Encefálica/diagnóstico , Infarto da Artéria Cerebral Média/diagnóstico , Animais , Biomarcadores/sangue , Encéfalo/diagnóstico por imagem , Isquemia Encefálica/sangue , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/genética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Infarto da Artéria Cerebral Média/sangue , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/genética , Macaca mulatta , Imageamento por Ressonância Magnética , Masculino , Transcriptoma/fisiologia
17.
Proteomics ; 8(11): 2244-55, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18452231

RESUMO

To identify proteins involved in cellular adaptive responses to zinc, a comparative proteome analysis between a previously developed high zinc- and cadmium-resistant human epithelial cell line (high zinc-resistant HeLa cells, HZR) and the parental HeLa cells has been carried out. Differentially produced proteins included cochaperones, proteins associated with oxido-reductase activities, and ubiquitin. Biochemical pathways to which these proteins belong were probed for their involvement in the resistance of both cell lines against cadmium toxicity. Among ER stressors, thapsigargin sensitized HZR cells, but not HeLa cells, to cadmium toxicity more acutely than tunicamycin, implying that these cells heavily relied on proper intracellular calcium distribution. The similar sensitivity of both HeLa and HZR cells to inhibitors of the proteasome, such as MG-132 or lactacystin, excluded improved proteasome activity as a mechanism associated with zinc adaptation of HZR cells. The enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD) was overproduced in HZR cells as compared to HeLa cells. It transforms HPP to homogentisate in the second step of tyrosine catabolism. Inhibition of HPPD decreased the resistance of HZR cells against cadmium, but not that of HeLa cells, suggesting that adaptation to zinc overload and increased HPP removal are linked in HZR cells.


Assuntos
Cádmio/toxicidade , Proteômica/métodos , Zinco/química , 4-Hidroxifenilpiruvato Dioxigenase/metabolismo , Cádmio/química , Cádmio/farmacologia , Intoxicação por Cádmio/metabolismo , Anidrases Carbônicas/metabolismo , Sobrevivência Celular , Relação Dose-Resposta a Droga , Eletroforese em Gel Bidimensional , Células Epiteliais/citologia , Células HeLa , Humanos , Proteoma , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia
18.
Int J Biochem Cell Biol ; 40(6-7): 1111-25, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18343183

RESUMO

The mammalian secretory proprotein convertases are part of a family of nine serine proteinases of the subtilisin-type. Seven of them cleave after basic amino acids and are called PC1/3, PC2, furin, PC4, PC5/6, PACE4 and PC7. The two other convertases SKI-1/S1P and PCSK9 are implicated in cholesterol and/or fatty acid metabolism. The convertases PC5/6 and PACE4 are activated at the cell surface where they are tethered to heparan sulfate proteoglycans. This activation pathway is unique and differs from that of furin and PC7, which are activated in the trans-Golgi network and from PC1/3 and PC2 that are activated in dense core secretory granules. While some of the basic amino acid-specific convertases may display redundant cleavages of substrates, they uniquely process certain substrates in vivo. Indeed, the conditional knockout of the PC5/6 gene in the embryo proper in mice led to severe malformations, bone morphogenic defects and death at birth. This is likely due to the absence of processing of the growth differentiating factor 11 (Gdf11). Both complete and liver-specific knockout of Pcsk9 revealed that it is a major convertase that regulates the level of circulating low-density lipoproteins (LDL) via the degradation of the hepatic LDL-receptor. This apparently non-enzymatic mechanism implicates the enhanced degradation of the LDLR in endosomes/lysosomes. These data provide evidence that an inhibitor of PCSK9-LDLR interaction is a viable target for the development of a novel cholesterol lowering drug in conjunction with the classical statins.


Assuntos
Pró-Proteína Convertases/fisiologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência Consenso , Ativação Enzimática , Humanos , Dados de Sequência Molecular , Pró-Proteína Convertases/química , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
19.
J Cereb Blood Flow Metab ; 38(6): 1070-1084, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28569655

RESUMO

Stroke is a devastating disorder that significantly contributes to death, disability and healthcare costs. In ischemic stroke, the only current acute therapy is recanalization, but the narrow therapeutic window less than 6 h limits its application. The current challenge is to prevent late cell death, with concomitant therapy targeting the ischemic cascade to widen the therapeutic window. Among potential neuroprotective drugs, cyclin-dependent kinase inhibitors such as (S)-roscovitine are of particular relevance. We previously showed that (S)-roscovitine crossed the blood-brain barrier and was neuroprotective in a dose-dependent manner in two models of middle cerebral artery occlusion (MCAo). According to the Stroke Therapy Academic Industry Roundtable guidelines, the pharmacokinetics of (S)-roscovitine and the optimal mode of delivery and therapeutic dose in rats were investigated. Combination of intravenous (IV) and continuous sub-cutaneous (SC) infusion led to early and sustained delivery of (S)-roscovitine. Furthermore, in a randomized blind study on a transient MCAo rat model, we showed that this mode of delivery reduced both infarct and edema volume and was beneficial to neurological outcome. Within the framework of preclinical studies for stroke therapy development, we here provide data to improve translation of pre-clinical studies into successful clinical human trials.


Assuntos
Edema Encefálico , Isquemia Encefálica , Fármacos Neuroprotetores , Recuperação de Função Fisiológica/efeitos dos fármacos , Roscovitina , Animais , Edema Encefálico/tratamento farmacológico , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Edema Encefálico/fisiopatologia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Masculino , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Roscovitina/farmacocinética , Roscovitina/farmacologia
20.
Vet Immunol Immunopathol ; 203: 57-59, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30243374

RESUMO

Veterinary medical examinations, including both physical examination and diagnostic tests, are important to monitor the health of both managed-care and wild marine mammals. However, limited species-specific reagents and assays are available that may contribute to a broader medical examination. This project evaluated if commercially available human and porcine antibodies and reagents would cross-react with manatee (Trichechus manatus) cytokines as the first step to validate a new diagnostic tool for manatees. Overall, as a result of limited cross-reactivity, human and porcine commercial reagents did not allow for the quantification of manatee cytokines. At this point, caution must be exercised when using human or porcine immunoassay reagents to quantify manatee cytokines if the reagents have not been fully validated. Future efforts will continue to explore and test the cross-reactivity of reagents to measure manatee cytokines as new species-specific and commercial reagents become available.


Assuntos
Citocinas/sangue , Indicadores e Reagentes/uso terapêutico , Trichechus manatus/imunologia , Animais , Reações Cruzadas/imunologia , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Interleucinas/sangue , Interleucinas/imunologia , Leucócitos Mononucleares/imunologia , Reação em Cadeia da Polimerase/veterinária , Suínos , Trichechus manatus/sangue
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