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1.
Mol Ther Nucleic Acids ; 29: 625-642, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36090761

RESUMO

Tau is a microtubule-associated protein (MAPT, tau) implicated in the pathogenesis of tauopathies, a spectrum of neurodegenerative disorders characterized by accumulation of hyperphosphorylated, aggregated tau. Because tau pathology can be distinct across diseases, a pragmatic therapeutic approach may be to intervene at the level of the tau transcript, as it makes no assumptions to mechanisms of tau toxicity. Here we performed a large library screen of locked-nucleic-acid (LNA)-modified antisense oligonucleotides (ASOs), where careful tiling of the MAPT locus resulted in the identification of hot spots for activity in the 3' UTR. Further modifications to the LNA design resulted in the generation of ASO-001933, which selectively and potently reduces tau in primary cultures from hTau mice, monkey, and human neurons. ASO-001933 was well tolerated and produced a robust, long-lasting reduction in tau protein in both mouse and cynomolgus monkey brain. In monkey, tau protein reduction was maintained in brain for 20 weeks post injection and corresponded with tau protein reduction in the cerebrospinal fluid (CSF). Our results demonstrate that LNA-ASOs exhibit excellent drug-like properties and sustained efficacy likely translating to infrequent, intrathecal dosing in patients. These data further support the development of LNA-ASOs against tau for the treatment of tauopathies.

2.
Acta Neuropathol ; 131(5): 775-91, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26860727

RESUMO

Cell-based therapies are emerging as new promising treatments in stroke. However, their functional mechanism and therapeutic potential during early infarct maturation has so far received little attention. Here, we asked if cell-based delivery of the interleukin-1 receptor antagonist (IL-1Ra), a known neuroprotectant in stroke, can promote neuroprotection, by modulating the detrimental inflammatory response in the tissue at risk. We show by the use of IL-1Ra-overexpressing and IL-1Ra-deficient mice that IL-1Ra is neuroprotective in stroke. Characterization of the cellular and spatiotemporal production of IL-1Ra and IL-1α/ß identifies microglia, not infiltrating leukocytes, as the major sources of IL-1Ra after experimental stroke, and shows IL-1Ra and IL-1ß to be produced by segregated subsets of microglia with a small proportion of these cells co-expressing IL-1α. Reconstitution of whole body irradiated mice with IL-1Ra-producing bone marrow cells is associated with neuroprotection and recruitment of IL-1Ra-producing leukocytes after stroke. Neuroprotection is also achieved by therapeutic injection of IL-1Ra-producing bone marrow cells 30 min after stroke onset, additionally improving the functional outcome in two different stroke models. The IL-1Ra-producing bone marrow cells increase the number of IL-1Ra-producing microglia, reduce the availability of IL-1ß, and modulate mitogen-activated protein kinase (MAPK) signaling in the ischemic cortex. The importance of these results is underlined by demonstration of IL-1Ra-producing cells in the human cortex early after ischemic stroke. Taken together, our results attribute distinct neuroprotective or neurotoxic functions to segregated subsets of microglia and suggest that treatment strategies increasing the production of IL-1Ra by infiltrating leukocytes or microglia may also be neuroprotective if applied early after stroke onset in patients.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/terapia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Infarto Encefálico , Modelos Animais de Doenças , Comportamento Exploratório , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Proteína Glial Fibrilar Ácida , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Força Muscular/genética , Força Muscular/fisiologia , Acidente Vascular Cerebral/genética , Fatores de Tempo
3.
J Neuroinflammation ; 11: 123, 2014 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-25038795

RESUMO

BACKGROUND: Crosstalk between the immune system in the brain and the periphery may contribute to the long-term outcome both in experimental and clinical stroke. Although, the immune defense collectin surfactant protein-D (SP-D) is best known for its role in pulmonary innate immunity, SP-D is also known to be involved in extrapulmonary modulation of inflammation in mice. We investigated whether SP-D affected cerebral ischemic infarction and ischemia-induced inflammatory responses in mice. METHODS: The effect of SP-D was studied by comparing the size of ischemic infarction and the inflammatory and astroglial responses in SP-D knock out (KO) and wild type (WT) mice subjected to permanent middle cerebral artery occlusion. SP-D mRNA production was assessed in isolated cerebral arteries and in the whole brain by PCR, and SP-D protein in normal appearing and ischemic human brain by immunohistochemistry. Changes in plasma SP-D and TNF were assessed by ELISA and proximity ligation assay, respectively. RESULTS: Infarct volumetric analysis showed that ablation of SP-D had no effect on ischemic infarction one and five days after induction of ischemia. Further, ablation of SP-D had no effect on the ischemia-induced increase in TNF mRNA production one day after induction of ischemia; however the TNF response to the ischemic insult was affected at five days. SP-D mRNA was not detected in parenchymal brain cells in either naïve mice or in mice subjected to focal cerebral ischemia. However, SP-D mRNA was detected in middle cerebral artery cells in WT mice and SP-D protein in vascular cells both in normal appearing and ischemic human brain tissue. Measurements of the levels of SP-D and TNF in plasma in mice suggested that levels were unaffected by the ischemic insult. Microglial-leukocyte and astroglial responses were comparable in SP-D KO and WT mice. CONCLUSIONS: SP-D synthesis in middle cerebral artery cells is consistent with SP-D conceivably leaking into the infarcted area and affecting local cytokine production. However, there was no SP-D synthesis in parenchymal brain cells and ablation of SP-D had no effect on ischemic cerebral infarction.


Assuntos
Infarto Cerebral/metabolismo , Proteína D Associada a Surfactante Pulmonar/sangue , Proteína D Associada a Surfactante Pulmonar/deficiência , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Antígeno CD11b/metabolismo , Artérias Cerebrais/metabolismo , Artérias Cerebrais/patologia , Infarto Cerebral/etiologia , Infarto Cerebral/patologia , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Infarto da Artéria Cerebral Média/complicações , Antígenos Comuns de Leucócito/metabolismo , Leucócitos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/efeitos dos fármacos , Microglia/metabolismo , Proteína D Associada a Surfactante Pulmonar/genética , Fatores de Tempo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
4.
Environ Health Perspect ; 122(4): 345-50, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24380925

RESUMO

BACKGROUND: Filaggrin is an epidermal protein that is crucial for skin barrier function. Up to 10% of Europeans and 5% of Asians carry at least one null allele in the filaggrin gene (FLG). Reduced expression of filaggrin in carriers of the null allele is associated with facilitated transfer of allergens across the epidermis. We hypothesized that these individuals may have increased transdermal uptake of endocrine disruptors, including phthalates. OBJECTIVES: We investigated urinary excretion of phthalate metabolites and testicular function in young men with and without FLG loss-of-function variants in a cross-sectional study of 861 young men from the general Danish population. METHODS: All men were genotyped for FLG R501X, 2282del4, and R2447X loss-of-function variants. We measured urinary concentrations of 14 phthalate metabolites and serum levels of reproductive hormones. We also evaluated semen quality. RESULTS: Sixty-five men (7.5%) carried at least one FLG-null allele. FLG-null carriers had significantly higher urinary concentrations of several phthalate metabolites, including a 33% higher concentration of MnBP (mono-n-butyl phthalate; 95% CI: 16, 51%). FLG-null variants were not significantly associated with reproductive hormones or semen quality parameters. CONCLUSION: This study provides evidence that carriers of FLG loss-of-function alleles may have higher internal exposure to phthalates, possibly due to increased transepidermal absorption. FLG loss-of-function variants may indicate susceptible populations for which special attention to transepidermal absorption of chemicals and medication may be warranted.


Assuntos
Proteínas de Filamentos Intermediários/genética , Ácidos Ftálicos/urina , Testículo/fisiologia , Adolescente , Adulto , Estudos Transversais , Proteínas Filagrinas , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Ácidos Ftálicos/metabolismo , Adulto Jovem
5.
PLoS One ; 8(12): e84293, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367652

RESUMO

BACKGROUND: Common loss-of-function mutations in the filaggrin gene (FLG) are a major predisposing risk factor for atopic disease due to reduced epidermal filaggrin protein levels. We previously observed an association between these mutations and type 2 diabetes and hypothesized that an inherited impairment of skin barrier functions could facilitate low-grade inflammation and hence increase the risk of diabetes and cardiovascular disease. We examined the association between loss-of-function mutations in FLG and diabetes, stroke, ischemic heart disease (IHD), and all-cause mortality in the general population. METHODS: The R501X and 2282del4 loss-of function mutations in FLG were genotyped in four Danish study populations including a total of 13373 adults aged 15-77 years. Two of the studies also genotyped the R2447X mutation. By linkage to Danish national central registers we obtained information for all participants on dates of diagnoses of diabetes, stroke, and IHD, as well as all-cause mortality. Data were analyzed by Cox proportional hazard models and combined by fixed effect meta-analyses. RESULTS: In meta-analyses combining the results from the four individual studies, carriage of loss-of-function mutations in FLG was not associated with incident diabetes (hazard ratio (HR) (95% confidence intervals (CI)) = 0.95 (0.73, 1.23), stroke (HR (95% CI) = 1.27 (0.97, 1.65), ischemic heart disease (HR (95%CI) = 0.92 (0.71, 1.19), and all-cause mortality (HR (95%CI) = 1.02 (0.83, 1.25)). Similar results were obtained when including prevalent cases in logistic regression models. CONCLUSION: Our results suggest that loss-of-function mutations in FLG are not associated with type 2 diabetes, cardiovascular disease, and all-cause mortality. However, larger studies with longer follow-up are needed to exclude any associations.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteínas de Filamentos Intermediários/genética , Proteínas de Filamentos Intermediários/metabolismo , Mortalidade , Mutação , Isquemia Miocárdica/genética , Acidente Vascular Cerebral/genética , Adolescente , Adulto , Idoso , Dinamarca/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Proteínas Filagrinas , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Adulto Jovem
6.
Exp Dermatol ; 22(9): 572-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23947670

RESUMO

More than 40 null mutations in the filaggrin (FLG) gene are described. It is therefore possible to find two different null mutations in one individual (compound heterozygosity). It has been generally perceived that homozygous and compound heterozygous individuals were genotypically comparable; however, this has not been scientifically investigated. Two different FLG null mutations in the same individual may be in trans position, meaning that each mutation locates to a different allele functionally equivalent to homozygosity, or may be in cis position, meaning that both mutations locate to the same allele functionally equivalent to heterozygosity. To experimentally investigate allelic in cis versus in trans configuration of the two most common filaggrin (FLG) mutations (R501X and 2282del4) in compound heterozygous individuals. Testing for in cis or in trans allele configuration was performed by means of allele-specific PCR amplification and analysis of PCR products by agarose gel electrophoresis. All R501X/2282del4 compound heterozygous samples collected over a 4-year period of routine FLG mutation testing were investigated. In total, 37 samples were tested. All thirty-seven R501X/2282del4 compound heterozygous individuals were found to carry the two mutations in trans position. FLG null mutation compound heterozygous individuals can be considered functionally equivalent to FLG null mutation homozygosity for any of the two mutations.


Assuntos
Proteínas de Filamentos Intermediários/genética , Proteínas Mutantes/genética , Mutação , Alelos , Análise Mutacional de DNA , Proteínas Filagrinas , Genótipo , Heterozigoto , Homozigoto , Humanos , Proteínas de Filamentos Intermediários/deficiência , Dermatopatias Genéticas/genética
7.
Nucleic Acid Ther ; 23(5): 302-10, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23952551

RESUMO

Antisense oligonucleotides that recruit RNase H and thereby cleave complementary messenger RNAs are being developed as therapeutics. Dose-dependent hepatic changes associated with hepatocyte necrosis and increases in serum alanine-aminotransferase levels have been observed after treatment with certain oligonucleotides. Although general mechanisms for drug-induced hepatic injury are known, the characteristics of oligonucleotides that determine their hepatotoxic potential are not well understood. Here, we present a comprehensive analysis of the hepatotoxic potential of locked nucleic acid-modified oligonucleotides in mice. We developed a random forests classifier, in which oligonucleotides are regarded as being composed of dinucleotide units, which distinguished between 206 oligonucleotides with high and low hepatotoxic potential with 80% accuracy as estimated by out-of-bag validation. In a validation set, 17 out of 23 oligonucleotides were correctly predicted (74% accuracy). In isolation, some dinucleotide units increase, and others decrease, the hepatotoxic potential of the oligonucleotides within which they are found. However, a complex interplay between all parts of an oligonucleotide can influence the hepatotoxic potential. Using the classifier, we demonstrate how an oligonucleotide with otherwise high hepatotoxic potential can be efficiently redesigned to abate hepatotoxic potential. These insights establish analysis of sequence and modification patterns as a powerful tool in the preclinical discovery process for oligonucleotide-based medicines.


Assuntos
Alanina Transaminase/sangue , Desenho de Fármacos , Fígado/efeitos dos fármacos , Oligonucleotídeos Antissenso/toxicidade , Oligonucleotídeos/toxicidade , Oligonucleotídeos Fosforotioatos/toxicidade , Algoritmos , Animais , Peso Corporal , Feminino , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Conformação de Ácido Nucleico , Oligonucleotídeos/administração & dosagem , Oligonucleotídeos/síntese química , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/síntese química , Tamanho do Órgão , Oligonucleotídeos Fosforotioatos/administração & dosagem , Oligonucleotídeos Fosforotioatos/síntese química , Valor Preditivo dos Testes , Relação Quantitativa Estrutura-Atividade
8.
Contact Dermatitis ; 69(6): 355-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23808934

RESUMO

BACKGROUND: Loss-of-function mutations in the filaggrin gene (FLG) are associated with xerosis, atopic dermatitis, and early onset of hand eczema. Irritant exposure is a risk factor for occupational hand eczema, and FLG mutations increase the risk of occupational irritant contact dermatitis on the hands in hospital cohorts. It is unknown whether FLG mutations affect the level of irritant exposure. OBJECTIVES: To evaluate whether exposure to occupational irritants was dependent on FLG mutations, atopic dermatitis, and age at hand eczema onset. METHODS: Randomly chosen Danish adults completed a questionnaire on general health and occupational exposures. Genotyping for FLG mutations (R501X, 2282del4, and R2447X) and patch testing were performed. RESULTS: Overall, 38.7% of subjects reported present or previous occupational exposure to irritants. Among individuals who reported hand eczema onset before entering their work life, 50.6% (45/89) of FLG non-mutation carriers became exposed to irritants, as compared with 28.6% (4/14) of heterozygous and 0% (0/6) of homozygous mutation carriers (p = 0.006). Avoidance was conspicuous among mutation carriers reporting childhood hand eczema and atopic dermatitis (odds ratio 0.08, 95% confidence interval 0.01-0.65). CONCLUSIONS: Carriers of FLG mutations who have had hand eczema onset in childhood avoid occupational exposure to irritants; the association is most marked with homozygous mutation status combined with atopic dermatitis.


Assuntos
Dermatite Atópica/genética , Dermatite Irritante/genética , Dermatite Ocupacional/genética , Heterozigoto , Proteínas de Filamentos Intermediários/genética , Mutação , Exposição Ocupacional/estatística & dados numéricos , Adolescente , Adulto , Idade de Início , Idoso , Aprendizagem da Esquiva , Estudos Transversais , Dinamarca , Dermatite Atópica/diagnóstico , Dermatite Atópica/psicologia , Dermatite Irritante/diagnóstico , Dermatite Irritante/psicologia , Dermatite Ocupacional/diagnóstico , Dermatite Ocupacional/psicologia , Feminino , Proteínas Filagrinas , Marcadores Genéticos , Predisposição Genética para Doença , Técnicas de Genotipagem , Inquéritos Epidemiológicos , Homozigoto , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Inquéritos e Questionários , Adulto Jovem
9.
Contact Dermatitis ; 68(5): 273-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23343419

RESUMO

BACKGROUND: Although heterozygous filaggrin gene (FLG) mutation carriers seem to have an increased risk of atopic, irritant and allergic nickel dermatitis, it remains unclear whether the risk of contact sensitization to allergens other than nickel is also elevated in FLG mutation carriers. OBJECTIVES: We hypothesized that heterozygous FLG mutation carriers who suffer from dermatitis will have strongly reduced or even absent filaggrin levels during episodes of inflammation, potentially increasing the penetration of contact allergens, and hence the risk of becoming sensitized. MATERIALS AND METHODS: During 2006-2008, 3335 randomly invited 18-69-year-old adult Danes participated in a general health examination, filled out a questionnaire, and were genotyped for the R501X and 2282del4 mutations in FLG. RESULTS: A logistic regression analysis restricted to individuals who reported atopic dermatitis and frequent episodes of hand eczema showed a strong association between FLG mutations and contact sensitization to allergens other than nickel (odds ratio 5.71; 95% confidence interval 1.31-24.94). In participants without dermatitis, no association was found between contact sensitization and FLG mutations. CONCLUSION: FLG mutation carriers with self-reported dermatitis have an increased risk of contact sensitization to substances other than nickel, whereas FLG mutations alone may not, or may only slightly, increase the risk of sensitization.


Assuntos
Dermatite Atópica/genética , Dermatite de Contato/genética , Dermatite Irritante/genética , Proteínas de Filamentos Intermediários/genética , Mutação/genética , Adulto , Idoso , Análise Mutacional de DNA , Feminino , Proteínas Filagrinas , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro/métodos , Fenótipo , Medição de Risco , Fatores de Risco , Adulto Jovem
11.
Clin Chim Acta ; 413(19-20): 1488-92, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-22705401

RESUMO

BACKGROUND: The filaggrin protein is expressed as profilaggrin mainly in stratum granulosum cells of the epidermis. The profilaggrin gene codes for 10-12 filaggrin repeats. The filaggrin protein is important for skin barrier function. Filaggrin deficiency due to functional null-polymorphisms affects 8-10% of the people in Northern Europe and is a strong risk factor for several diseases. Here, we describe a novel method for efficient, multiplexed genotyping of variations in the profilaggrin gene. METHODS: Five known techniques were combined: i) allele-specific PCR, ii) PCR with tagged primers, iii) asymmetric PCR, iv) multiplex PCR, and v) hybridization of single-stranded PCR products to spectrally coded microbeads carrying tag sequences as capture probes. Asymmetry of PCR was accomplished by having the tagged and allele-specific forward primers present in limiting concentrations. Asymmetry ensured that the later PCR cycles generated only single-stranded reverse-strand products. This greatly improved the assay sensitivity and allowed for simple optimization. RESULTS: The specificity of the tags was verified with single PCR in wildtype and homozygous samples. Only the PCR products with the appropriate anti-tag hybridized to the corresponding beads, demonstrating the specificity of the signal. The hybridization signal is strongly dependent on single-stranded PCR products. After 46 PCR cycles, double-stranded products are clearly present, but only the single-stranded products generated in later cycles hybridize to the beads and elicit the strong signals that allow for unambiguous genotyping. CONCLUSIONS: We have tested 17,000 samples for three filaggrin polymorphisms using this method, with a call rate exceeding 99% and a reagent cost of US $ 0.75 per sample. The method is universally applicable for multiplex genotyping of e.g. hereditary hemochromatosis, lactose intolerance, or cystic fibrosis.


Assuntos
Técnicas de Genotipagem , Proteínas de Filamentos Intermediários/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Alelos , Biotinilação , Primers do DNA , DNA de Cadeia Simples , Proteínas Filagrinas , Humanos , Microesferas , Hibridização de Ácido Nucleico , Polimorfismo de Nucleotídeo Único , Isoformas de Proteínas/genética , Sensibilidade e Especificidade
12.
J Allergy Clin Immunol ; 129(2): 374-80, 380.e1-2, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22088612

RESUMO

BACKGROUND: The mechanisms underlying the association between filaggrin (FLG) deficiency and asthma are not known. It has been hypothesized that FLG deficiency leads to enhanced percutaneous exposure to environmental substances that might trigger immune responses. We hypothesized that interactions between FLG deficiency and environmental exposures play a role in asthma development. OBJECTIVE: We sought to investigate possible interactions between FLG null mutations and tobacco smoking in relation to asthma. METHODS: A total of 3471 adults from a general population sample participated in a health examination. Lung function and serum specific IgE levels to inhalant allergens were measured, and information on asthma and smoking was obtained by means of questionnaire. Participants were genotyped for the 2 most common FLG null mutations in white subjects: R501X and 2282del4. Another Danish population was used for replication. RESULTS: The FLG null mutation genotype was significantly associated with a higher prevalence of asthma and decreased FEV(1)/forced vital capacity ratio. In logistic regression analyses with asthma as the outcome, a significant interaction was found between FLG null mutations and smoking status (P = .02). This interaction was confirmed, although it was not statistically significant, in another Danish population study. Interactions between FLG genotype and cumulated smoking exposure were found in relation to asthma (P = .03) and decreased FEV(1)/forced vital capacity ratio (P = .03). A 3-way interaction was found among FLG genotype, smoking, and asthma, suggesting that the FLG-smoking interaction mainly played a role in nonatopic subjects. CONCLUSION: FLG null mutations modified the effects of smoking on the risk of asthma. This finding might have implications for risk stratification of the population.


Assuntos
Asma/genética , Proteínas de Filamentos Intermediários/genética , Fumar/genética , Adolescente , Adulto , Idoso , Asma/sangue , Asma/fisiopatologia , Dermatite Alérgica de Contato/sangue , Dermatite Alérgica de Contato/genética , Dermatite Alérgica de Contato/fisiopatologia , Feminino , Proteínas Filagrinas , Genótipo , Humanos , Hipersensibilidade Imediata/sangue , Hipersensibilidade Imediata/genética , Hipersensibilidade Imediata/fisiopatologia , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Mutação , Espirometria , Adulto Jovem
13.
BMJ Open ; 1(1): e000062, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22021744

RESUMO

Background Filaggrin proteins are located in the skin and prevent epidermal water loss and impede the entry of micro-organisms, allergens and chemicals. Filaggrin null mutations are strongly associated with ichthyosis vulgaris and atopic dermatitis. Objective The authors aimed to investigate the association between filaggrin null mutations, atopic dermatitis and diabetes. Design A random sample of 3335 adults from the general population in Denmark was filaggrin-genotyped for R501X and 2282del4 null-mutations and questioned about atopic dermatitis and diabetes. Furthermore, two independent study populations of patients with type 1 (n=104) or 2 (n=774) diabetes were genotyped. Results In a crude data analysis, a positive association was detected between the filaggrin null genotype and, respectively, subjects from the general population who reported diabetes (p=0.04) and patients with established type 2 diabetes (p=0.073). Adjustment for age and gender resulted in significant associations for patients with type 2 diabetes (p=0.048) and subjects with self-reported diabetes (p=0.032). Conclusions Adult Danes with a filaggrin null genotype had a significantly increased prevalence of self-reported diabetes. This finding was replicated when an independent sample of Danish patients with established type 2 diabetes was compared with control subjects from the general population.

14.
J Dent ; 39(2): 128-32, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21074596

RESUMO

OBJECTIVES: Natural rubber latex (NRL) contains over 200 proteins of which 13 have been identified as allergens and the cause of type I latex allergy. Health care workers share a high occupational risk for developing latex allergy. Filaggrin null mutations increase the risk of type I sensitizations to aeroallergens and it is possible that filaggrin null mutations also increase the risk of latex allergy. The aim of this paper was to examine the association between filaggrin null mutations and type I latex allergy. METHODS: Twenty latex allergic and 24 non-latex allergic dentists and dental assistants, occupationally exposed to latex, were genotyped for filaggrin null mutations R501X and 2282del4. Latex allergy was determined by a positive reaction or a historical positive reaction to a skin prick test with NRL. RESULTS: 41 individuals were successfully genotyped. Three individuals were filaggrin mutation carriers. One (2.4%) was a 2282del4 heterozygote and two (4.9%) were R501X heterozygote. No homozygote or compound heterozygote carriers were detected. No association between filaggrin null mutations and type I latex allergy was found (p=0.24). Patients with type I latex allergy more often reported contact dermatitis. CONCLUSIONS: This is the first study to examine a highly plausible association between filaggrin null mutations and type I latex allergy. The study subjects were occupationally exposed to latex but no association between latex allergy and filaggrin mutations were detected. Sensitization to latex in the cases in this study may not have occurred through direct skin contact but through the respiratory organs via latex proteins that are absorbed in glove powder and aerosolized.


Assuntos
Hipersensibilidade Imediata/genética , Proteínas de Filamentos Intermediários/genética , Hipersensibilidade ao Látex/genética , Mutação/genética , Precursores de Proteínas/genética , Aerossóis , Alérgenos , Arginina/genética , Assistentes de Odontologia , Odontólogos , Dermatite Alérgica de Contato/genética , Feminino , Proteínas Filagrinas , Predisposição Genética para Doença/genética , Genótipo , Heterozigoto , Humanos , Masculino , Doenças Profissionais/genética , Exposição Ocupacional , Deleção de Sequência/genética
15.
Contact Dermatitis ; 64(1): 24-31, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21166815

RESUMO

BACKGROUND: It was recently shown that filaggrin null mutation carrier status was associated with nickel allergy and self-reported intolerance to costume jewellery. Because of the biochemical characteristics of filaggrin, it may show nickel barrier properties in the stratum corneum. OBJECTIVES: To investigate whether subjects with filaggrin null mutations report nickel dermatitis at an earlier age than wild-type individuals, and to analyse whether null mutation carriers have stronger patch test reactivity to nickel sulfate than do wild-type individuals. MATERIALS: A total of 3471 Danes (18-69 years of age) answered a questionnaire about general health, and underwent patch testing and filaggrin genotyping. RESULTS: The mean number of years at risk of developing nickel dermatitis was significantly lower for the filaggrin null genotype than for the wild-type genotype when ear piercing status was considered. In positive patch test readings, the proportion of null mutants increased with increasing reaction strength. CONCLUSIONS: Filaggrin null mutations may lower the age of onset of nickel dermatitis. The hypothesis that ear piercings obscure the effect of filaggrin null mutations on the development of nickel allergy in statistical analyses was supported. An association between the null genotype and increased nickel sensitivity was indicated by patch test reading and questionnaire data.


Assuntos
Dermatite Alérgica de Contato/genética , Predisposição Genética para Doença , Proteínas de Filamentos Intermediários/genética , Mutação/genética , Níquel/toxicidade , Adolescente , Adulto , Idade de Início , Idoso , Estudos Transversais , Dinamarca/epidemiologia , Dermatite Alérgica de Contato/epidemiologia , Feminino , Proteínas Filagrinas , Genótipo , Heterozigoto , Humanos , Joias/toxicidade , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Inquéritos e Questionários , Adulto Jovem
17.
Contact Dermatitis ; 63(2): 89-95, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20629673

RESUMO

BACKGROUND: Filaggrin null (FLG) mutations lead to skin barrier disruption with a reduced resistance towards exogenous agents and also influence the course of disease in atopic dermatitis. OBJECTIVES: To examine the association between FLG mutations and contact allergy, polysensitization, hand eczema at first appearance of disease, occurrence, and course of dermatitis. METHODS: A venous blood sample from 430 individuals was genotyped for FLG mutations R501X and 2282del4 with polymerase chain reaction followed by typing through hybridization to paramagnetic polystyrene beads and analysis on a BioPlex 200. All individuals had a minimum of one positive patch test reaction. RESULTS: In all, 3.5% were 2282del4 heterozygote and 5.1% were R501X heterozygote. An odds ratio (OR) of 1.49 [95% confidence interval (CI) 0.74-3.00] was found for nickel allergy, OR 0.84 (95% CI 0.41-1.74) for polysensitization, OR 0.78 (95% CI 0.25-2.43) for dermatitis, OR 0.96 (95% CI 0.48-1.92) for hand eczema at debut, OR 1.25 (95% CI 0.99-1.57) for duration of disease, and OR 0.76 (95% CI 0.59-0.97) for age at onset. CONCLUSIONS: No association between nickel allergy, polysensitization, hand eczema at first appearance or occurrence of dermatitis, and FLG mutations was found. However, patients with FLG mutations had an earlier age of onset compared with the wild-type genotype and a trend towards longer duration of disease.


Assuntos
Dermatite Alérgica de Contato/genética , Proteínas de Filamentos Intermediários/genética , Mutação , Adulto , Idade de Início , Feminino , Proteínas Filagrinas , Predisposição Genética para Doença , Dermatoses da Mão/genética , Humanos , Proteínas de Filamentos Intermediários/sangue , Masculino , Pessoa de Meia-Idade
19.
J Neurosci ; 29(5): 1319-30, 2009 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19193879

RESUMO

Microglia and infiltrating leukocytes are considered major producers of tumor necrosis factor (TNF), which is a crucial player in cerebral ischemia and brain inflammation. We have identified a neuroprotective role for microglial-derived TNF in cerebral ischemia in mice. We show that cortical infarction and behavioral deficit are significantly exacerbated in TNF-knock-out (KO) mice compared with wild-type mice. By using in situ hybridization, immunohistochemistry, and green fluorescent protein bone marrow (BM)-chimeric mice, TNF was shown to be produced by microglia and infiltrating leukocytes. Additional analysis demonstrating that BM-chimeric TNF-KO mice grafted with wild-type BM cells developed larger infarcts than BM-chimeric wild-type mice grafted with TNF-KO BM cells provided evidence that the neuroprotective effect of TNF was attributable to microglial- not leukocyte-derived TNF. In addition, observation of increased infarction in TNF-p55 receptor (TNF-p55R)-KO mice compared with TNF-p75R and wild-type mice suggested that microglial-derived TNF exerts neuroprotective effects through TNF-p55R. We finally report that TNF deficiency is associated with reduced microglial population size and Toll-like receptor 2 expression in unmanipulated brain, which might also influence the neuronal response to injury. Our results identify microglia and microglial-derived TNF as playing a key role in determining the survival of endangered neurons in cerebral ischemia.


Assuntos
Isquemia Encefálica/patologia , Isquemia Encefálica/prevenção & controle , Microglia/metabolismo , Neurônios/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Animais , Isquemia Encefálica/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/patologia , Microglia/fisiologia , Neurônios/patologia , Fator de Necrose Tumoral alfa/fisiologia
20.
J Pharmacol Exp Ther ; 326(1): 338-47, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18445781

RESUMO

Recombinant human interferon-beta (rhIFN-beta) is the leading therapeutic intervention shown to change the cause of relapsing-remitting multiple sclerosis, and both a nonglycosylated and a significantly more active glycosylated variant of rhIFN-beta are used in treatment. This study investigates the function of the rhIFN-beta1a glycan moiety and its individual carbohydrate residues, using the myxovirus resistance (Mx) mRNA as a biomarker in Mx-congenic mice. We showed that the Mx mRNA level in blood leukocytes peaked 3 h after s.c. administration of rhIFN-beta1a. In addition, a clear dose-response relationship was confirmed, and the Mx response was shown to be receptor-mediated. Using specific glycosidases, different glycosylation analogs of rhIFN-beta1a were obtained, and their activities were determined. The glycosylated rhIFN-beta1a showed significantly higher activity than its deglycosylated counterpart, due to a protein stabilization/solubilization effect of the glycan. It is interesting to note that the terminating sialic acids were essential for these effects. Conclusively, the structure/bioactivity relationship of rhIFN-beta1a was determined in vivo, and it provided a novel insight into the role of the rhIFN-beta1a glycan and its carbohydrate residues. The possibilities of improving the pharmacological properties of rhIFN-beta1a using glycoengineering are discussed.


Assuntos
Glicoproteínas/fisiologia , Interferon beta/fisiologia , Polissacarídeos/fisiologia , Animais , Estabilidade de Medicamentos , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/genética , Glicoproteínas/química , Glicoproteínas/metabolismo , Glicosilação , Humanos , Interferon Tipo I/farmacologia , Interferon beta-1a , Interferon beta/química , Interferon beta/metabolismo , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Resistência a Myxovirus , Polissacarídeos/química , Polissacarídeos/metabolismo , Proteínas Recombinantes , Ácidos Siálicos/fisiologia , Relação Estrutura-Atividade
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