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1.
Nat Commun ; 14(1): 4575, 2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516771

RESUMO

Vaccination, especially with multiple doses, provides substantial population-level protection against COVID-19, but emerging variants of concern (VOC) and waning immunity represent significant risks at the individual level. Here we identify correlates of protection (COP) in a multicenter prospective study following 607 healthy individuals who received three doses of the Pfizer-BNT162b2 vaccine approximately six months prior to enrollment. We compared 242 individuals who received a fourth dose to 365 who did not. Within 90 days of enrollment, 239 individuals contracted COVID-19, 45% of the 3-dose group and 30% of the four-dose group. The fourth dose elicited a significant rise in antibody binding and neutralizing titers against multiple VOCs reducing the risk of symptomatic infection by 37% [95%CI, 15%-54%]. However, a group of individuals, characterized by low baseline titers of binding antibodies, remained susceptible to infection despite significantly increased neutralizing antibody titers upon boosting. A combination of reduced IgG levels to RBD mutants and reduced VOC-recognizing IgA antibodies represented the strongest COP in both the 3-dose group (HR = 6.34, p = 0.008) and four-dose group (HR = 8.14, p = 0.018). We validated our findings in an independent second cohort. In summary combination IgA and IgG baseline binding antibody levels may identify individuals most at risk from future infections.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacina BNT162 , Estudos Prospectivos , COVID-19/prevenção & controle , SARS-CoV-2 , Imunoglobulina A , Imunoglobulina G
2.
Medicine (Baltimore) ; 101(28): e29268, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35839005

RESUMO

We aimed to compare the reliability of laboratory blood tests using 2 sampling methods, via a peripheral venous catheter (PVC) vs direct venipuncture stab (DVS), we evaluated the effect of time elapsed since PVC insertion, PVC diameter, and administration of saline and/or antibiotic infusion through PVC on the blood test results. A prospective comparative study was conducted between May 2018 and July 2019. Patients aged ≥ 18 years and admitted to our department with a 20G/22G PVC inserted within the last 24 hours were enrolled. Blood samples were collected from each participant in the morning, and a second sample was drawn using PVC. Dependent variables included the percentage of hemolysis, failure rate, complete blood count, biochemical testing parameters, and coagulation functions. A total of 211 patients participated in the study. In total, 237 blood tests were conducted, of which 167 were performed on day 1 and the remaining on day 2, with a second blood sample collected from 26 patients on day 2. Twenty-one participants received 22G PVC, and 23 participants received active infusion. No significant differences were found in failure rates when each subgroup was compared with the primary day 1 group. The intraclass correlation coefficient indicated significant correlations among all the indices in all groups. Both blood sampling methods (PVC and direct venipuncture) can be used interchangeably for routine laboratory tests on days 1 and 2 after PVC insertion using 20G/22G PVC or infused PVC.


Assuntos
Cateterismo Periférico , Testes Hematológicos , Humanos , Cateterismo Periférico/métodos , Catéteres , Estudos Prospectivos , Reprodutibilidade dos Testes
3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22277626

RESUMO

Variants of concern (VOC) of SARS-CoV2 and waning immunity pose a serious global problem. Overall, vaccination and prior infection appear to provide significant protection to the majority of individuals, but some remain susceptible to infection and severe disease. Rigorously identifying a broad spectrum of correlates of protection (COP) is necessary to identify these susceptible populations. The extent to which additional booster doses provide protection is also poorly understood. To address this need, we conducted a multicenter prospective study assessing the association between serological profiles and the risk for SARS-CoV-2 infection, comparing those vaccinated with three to four doses of Pfizer BNT162b2 vaccine. Of 608 healthy adults, 365 received three doses and 243 received four doses. During the first 90 days of followup, 239 (39%) were infected, of whom 165/365 (45%) received 3 doses and 74/243 (30%) four doses. We found that the fourth dose elicited a significant rise in antibody binding and neutralizing titers against multiple variants, and reduced the risk of symptomatic infection by 37% [95% I, 15% - 54%]. We identified several parameters based on IgG and IgA binding that were COPs. The strongest association with infection risk was reduced IgG levels to RBD mutants and IgA levels to VOCs, which was a COP in the three-dose group (HR=6.34, p=0.008) and in the four-dose group (HR=8.14, p=0.018). A combination of two commercially available ELISA assays were also associated with protection in both groups (HR = 1.84, p = 0.002; HR = 2.01, p = 0.025, respectively). Most importantly, we identified a subset of individuals with low antibody levels after three doses of vaccine that responded with a significant boost in neutralizing antibody titers after a fourth dose, but were still at significantly increased susceptibility to infection when compared to those who had pre-existing high levels of neutralizing antibodies. Thus, we identify a highly susceptible population that remains susceptible despite apparent responsiveness to vaccines. Further, we develop several specific and sensitive COPs that show dramatic effect sizes and may be utilized to identify individuals most at risk from future exposures.

5.
J Steroid Biochem Mol Biol ; 188: 8-16, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30508646

RESUMO

Acute myeloid leukemia (AML) is one of the deadliest hematological malignancies without effective treatment for most patients. Vitamin D derivatives (VDDs) - active metabolites 1α,25-dihydroxyvitamin D2 (1,25D2) and 1α,25-dihydroxyvitamin D3 (1,25D3) and their analogs - are differentiation-inducing agents which have potential for the therapy of AML. However, calcemic toxicity of VDDs limits their clinical use at doses effective against cancer cells in vivo. Here, we demonstrate that in AML cell cultures, moderate pro-differentiation effects of low concentrations of VDDs can be synergistically enhanced by structurally distinct compounds known to activate the transcription factor Nuclear Factor (Erythroid-derived 2)-Like 2 (NFE2L2 or Nrf2). Particularly, dimethyl fumarate (DMF), which is clinically approved for the treatment of multiple sclerosis and psoriasis, strongly cooperated with 1,25D3, PRI-5100 (19-nor-1,25D2; paricalcitol) and PRI-5202 (a double-point modified 19-nor analog of 1,25D2). The pro-differentiation synergy between VDDs (1,25D3 or PRI-5202) and Nrf2 activators (DMF, tert-butylhydroquinone or carnosic acid) was associated with a cooperative upregulation of the protein levels of the vitamin D receptor (VDR) and Nrf2 as well as increased mRNA expression of their respective target genes. These data support the notion that VDDs and Nrf2 activators synergize in inducing myeloid cell differentiation through the cooperative activation of the VDR and Nrf2/antioxidant response element signaling pathways. We have previously reported that PRI-5202 is more potent by approximately two orders of magnitude than 1,25D3 as a differentiation inducer in AML cell lines. In this study, we found that PRI-5202 was also at least 5-fold less calcemic in healthy mice compared to both its direct precursor PRI-1907 and 1,25D3. In addition, PRI-5202 was remarkably more resistant against degradation by the human 25-hydroxyvitamin D3-24-hydroxylase than both 1,25D2 and 1,25D3. Importantly, using a xenograft mouse model we demonstrated that co-administration of PRI-5202 and DMF resulted in a marked cooperative inhibition of human AML tumor growth without inducing treatment toxicity. Collectively, our findings provide a rationale for clinical testing of low-toxic VDD/DMF combinations as a novel approach for differentiation therapy of AML.


Assuntos
Fumarato de Dimetilo/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Receptores de Calcitriol/metabolismo , Vitamina D/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Fumarato de Dimetilo/farmacologia , Sinergismo Farmacológico , Feminino , Humanos , Leucemia/metabolismo , Leucemia/patologia , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Camundongos Endogâmicos ICR , Transdução de Sinais/efeitos dos fármacos , Vitamina D/análogos & derivados , Vitamina D/farmacologia , Vitaminas/química , Vitaminas/farmacologia , Vitaminas/uso terapêutico
6.
Cancer Genet ; 226-227: 1-10, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30005848

RESUMO

BACKGROUND: Early detection decreases lung cancer mortality. The Target-FISH Lung Cancer Detection (LCD) Test is a non-invasive test designed to detect chromosomal changes (deletion or amplification) via Fluorescence in situ Hybridization (FISH) in sputum specimens from persons suspected of having lung cancer. We evaluated the performance of the LCD test in patients with highly suspicious pulmonary nodules who were scheduled for a biopsy procedure. METHODS: Induced sputum was collected from patients who were scheduled for biopsy of a solitary pulmonary nodule (0.8-3 cm) in one of 6 tertiary medical centers in the US and Israel. The lung cancer detection (LCD) Test combined sputum cytology and Target-FISH analysis on the same target cells and the results were compared to the pathology. Participants with non-surgical negative biopsy results were followed for 2 years to determine their final diagnosis. RESULTS: Of the 173 participants who were evaluated, 112 were available for analysis. Overall, the LCD test had a sensitivity of 85.5% (95% CI, 76.1-92.3), specificity of 69% (95% CI, 49.2-84.7) and an accuracy of 81.3% (95% CI, 72.8-88). The positive and negative predictive values (PPV, NPV) were 88.8% and 62.5%, respectively. The LCD test was positive in 9 of 11 lung cancer patients who had an initial negative biopsy. CONCLUSIONS: In a cohort of patients with highly suspicious lung nodules, the LCD test is a non-invasive option with good sensitivity and a high positive predictive value. A positive LCD test reinforces the need to aggressively pursue a definitive diagnosis of suspicious nodules.


Assuntos
Citodiagnóstico/métodos , Detecção Precoce de Câncer/métodos , Hibridização in Situ Fluorescente/métodos , Neoplasias Pulmonares/diagnóstico , Escarro/citologia , Idoso , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Nódulo Pulmonar Solitário/diagnóstico , Nódulo Pulmonar Solitário/patologia
7.
Toxicon ; 68: 1-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23499925

RESUMO

Scorpion sting may cause myocardial injury and heart failure (HF). Clinical signs of failure may develop several hours or even days after the sting, while electrocardiography (ECG) and blood examination soon after the sting may be normal. We sought to examine whether normal echocardiographic (echo) examination performed shortly after hospital arrival would exclude subsequent HF. We also sought to check if blood troponin and natriuretic peptide values measured shortly after arrival may predict or exclude subsequent HF. Natriuretic peptide activities have not been measured in scorpion sting victims. We also wanted to check if HF occurs in envenomated young infants. In a 3-year prospective study we looked at the demographic, clinical, laboratory, ECG, and echo data of all patients with general envenomation who arrived at the emergency department (ED) after scorpion sting. Clinical, laboratory, ECG, and echo results on arrival and 24 h after arrival were checked and compared between groups of patients with normal and abnormal echo on arrival. We then looked for differences in clinical course, therapy, and outcome between groups. The study included 98 children aged 80 days to 19 years (median 53.1 months), 25 were below the age of 2 years. Envenomation by the "yellow scorpion"Leiurus quinquestriatus was suspected in 74 cases. Median time between sting and ED arrival was 80 min. Echo was performed on arrival in 93 of the 98 patients, (in 5 occasions it was not performed or not recorded) 74 were normal and 19 were abnormal. Abnormal echo included hypokinesia and low fractional shortening and ejection fraction of the left ventricle. Clinical signs, abnormal ECG, and laboratory results were not discriminative between groups on arrival. Mean troponin T was higher in patients with abnormal echo, but within normal range in 13 of the 19 patients with abnormal echo and above normal in 2 of the 74 patients with normal echo-missing sensitivity and specificity. Mean N-terminal pro B-type natriuretic peptide was above normal in both groups but within normal range in 5 patients with abnormal echo and above normal range in 24 patients with normal echo-missing sensitivity and specificity. None of the patients with normal echo had subsequent HF and none of the children younger than 2 years of age had HF. All patients survived the intoxication and were discharged home without sequel. We conclude that early echo examination is an important procedure. In our study, normal examination excluded subsequent HF. Abnormal examination accelerated cardiac therapy which might have contributed to our favorable outcome. HF did not occur in infants younger than two years of age.


Assuntos
Mordeduras e Picadas/metabolismo , Ecocardiografia , Insuficiência Cardíaca/diagnóstico , Venenos de Escorpião/efeitos adversos , Adolescente , Fator Natriurético Atrial/sangue , Mordeduras e Picadas/complicações , Criança , Pré-Escolar , Diagnóstico Precoce , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Lactente , Masculino , Estudos Prospectivos , Precursores de Proteínas/sangue , Troponina/sangue , Adulto Jovem
8.
Otolaryngol Head Neck Surg ; 147(3): 472-4, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22547556

RESUMO

OBJECTIVES: To study the relationship between peritonsillar abscess (PTA) and minor salivary glands surrounding the palatine tonsils. STUDY DESIGN: Prospective population-based study. SETTINGS: Tertiary care university hospital. SUBJECTS AND METHOD: Prospective study including 41 patients with PTA and 6 patients with a neck abscess. Amylase levels of the pus and serum were measured and compared between the 2 groups. Clinical data regarding hospitalization length and recurrence rate were also collected. RESULTS: Of the 41 patients with PTA, 7 suffered from recurrent PTA. Average level of amylase in the pus of the PTA group was 3841 U/L versus 7.7 U/L in the neck abscess group (P < .001; median, 62 vs 9.5). Serum amylase was higher in the PTA group (49.3 U/L vs 37.3 U/L; P = .008). There were no recurrences in PTA patients with amylase greater than 65 U/dL in the pus in 0 of 20 (0%) versus 7 of 21 (33%) for amylase lower than 65 U/L (P = .01). CONCLUSION: High amylase in the pus lends further support for involvement of minor salivary glands. However, high recurrence rates related to low amylase in the pus imply an additional pathogenesis possibly related to tonsillar infection. It is possible that both minor salivary glands as well as tonsillar infection play a role in the pathogenesis of peritonsillar infections.


Assuntos
Amilases/sangue , Abscesso Peritonsilar/fisiopatologia , Glândulas Salivares Menores/fisiopatologia , Abscesso/fisiopatologia , Humanos , Tempo de Internação , Pescoço , Estudos Prospectivos , Recidiva , Supuração/sangue
9.
J Mol Diagn ; 12(6): 771-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20864637

RESUMO

The definitive identification of malignant pleural mesothelioma (MPM) has significant clinical implications, yet other malignancies often involve the lung pleura, confounding the diagnosis of MPM. In the absence of accurate markers, MPM can be difficult to distinguish from peripheral lung adenocarcinoma and metastatic epithelial cancers. MicroRNA expression is tissue-specific and highly informative for identifying tumor origin. We identified microRNA biomarkers for the differential diagnosis of MPM and developed a standardized microRNA-based assay. Formalin-fixed, paraffin-embedded samples of 33 MPM and 210 carcinomas were used for assay development. Using microarrays, we identified microRNAs differentially expressed between MPM and various carcinomas. Hsa-miR-193-3p was overexpressed in MPM, while hsa-miR-200c and hsa-miR-192 were overexpressed in peripheral lung adenocarcinoma and carcinomas that frequently metastasize to lung pleura. We developed a standardized diagnostic assay based on the expression of these microRNAs. The assay reached a sensitivity of 100% and a specificity of 94% in a blinded validation set of 68 samples from the lung and pleura. This diagnostic assay can provide a useful tool in the differential diagnosis of MPM from other malignancies in the pleura.


Assuntos
Biomarcadores Tumorais/genética , Mesotelioma , MicroRNAs/genética , Análise em Microsséries/métodos , Neoplasias Pleurais , Regulação Neoplásica da Expressão Gênica , Humanos , Mesotelioma/diagnóstico , Mesotelioma/genética , Mesotelioma/patologia , MicroRNAs/metabolismo , Análise em Microsséries/normas , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/genética , Neoplasias Pleurais/patologia , Sensibilidade e Especificidade
10.
Int J Biochem Cell Biol ; 42(8): 1355-62, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20619223

RESUMO

Distinguishing hepatocellular carcinoma from metastatic tumors in the liver is of great practical importance, with significant therapeutic and prognostic implications. This differential diagnosis can be difficult because metastatic cancers in the liver, especially adenocarcinomas, may mimic the morphology and immunoexpression of hepatocellular carcinoma. Biomarkers that are specifically expressed in either hepatocellular carcinoma or metastatic adenocarcinoma can therefore be useful diagnostic tools. To find such biomarkers, we studied microRNA expression in 144 tumor samples using custom microarrays. Hsa-miR-141 and hsa-miR-200c, microRNAs that promote epithelial phenotypes, had significantly higher levels in non-hepatic epithelial tumors. In contrast, endothelial-associated hsa-miR-126 showed higher expression levels in hepatocellular carcinomas. Combinations of these microRNAs accurately identified primary hepatocellular carcinoma from metastatic adenocarcinoma in the liver. These findings were validated using quantitative real-time PCR to measure microRNA expression in additional samples. Thus, the tissue-specific expression patterns of microRNAs make them useful biomarkers for the diagnosis of liver malignancies.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Fígado/metabolismo , MicroRNAs/genética , Carcinoma Hepatocelular/patologia , Diagnóstico Diferencial , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Metástase Neoplásica , Curva ROC , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Nucleic Acids Res ; 38(18): 6234-46, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20483914

RESUMO

MicroRNAs (miRNAs) are ∼22-nt long, non-coding RNAs that regulate gene silencing. It is known that many human miRNAs are deregulated in numerous types of tumors. Here we report the sequencing of small RNAs (17-25 nt) from 23 breast, bladder, colon and lung tumor samples using high throughput sequencing. We identified 49 novel miRNA and miR-sized small RNAs. We further validated the expression of 10 novel small RNAs in 31 different types of blood, normal and tumor tissue samples using two independent platforms, namely microarray and RT-PCR. Some of the novel sequences show a large difference in expression between tumor and tumor-adjacent tissues, between different tumor stages, or between different tumor types. We also report the identification of novel small RNA classes in human: highly expressed small RNA derived from Y-RNA and endogenous siRNA. Finally, we identified dozens of new miRNA sequence variants that demonstrate the existence of miRNA-related SNP or post-transcriptional modifications. Our work extends the current knowledge of the tumor small RNA transcriptome and provides novel candidates for molecular biomarkers and drug targets.


Assuntos
MicroRNAs/metabolismo , Neoplasias/genética , RNA Neoplásico/metabolismo , RNA não Traduzido/metabolismo , Humanos , MicroRNAs/química , Neoplasias/metabolismo , RNA Neoplásico/química , RNA não Traduzido/química , Análise de Sequência de RNA
12.
Pathol Res Pract ; 206(8): 578-84, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20418022

RESUMO

For surgical pathologists, distinguishing whether a pulmonary neoplasm is primary or metastatic can be challenging, and current biomarkers do not always aid lung tumor classification. The tissue-associated expression of microRNA likely explains the remarkable finding that many tumors can be classified based solely on their microRNA expression signature. Here we show that microRNAs can serve as biomarkers for lung tumor classification. Using microRNA microarray data generated from 76 formalin-fixed, paraffin-embedded (FFPE) samples of either primary lung cancer or metastatic tumors to the lung, we have identified a set of microRNAs expressed differentially between these two groups. This set includes hsa-miR-182, which was most strongly over-expressed in the lung primary tumors, and hsa-miR-126, which was over-expressed in the metastatic tumors. The differential expression of this set of microRNAs was confirmed using qRT-PCR on a set of 54 samples. In light of our data, microRNA expression should be considered as a potential clinical biomarker for surgical pathologists faced with discerning the tumor type of an inscrutable lung neoplasm.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Diagnóstico Diferencial , Humanos , MicroRNAs , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
J Steroid Biochem Mol Biol ; 103(3-5): 558-62, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17267205

RESUMO

In a previous study we demonstrated a down-regulatory effect of vitamin D active metabolite (1,25(OH)(2)D(3)) and its vitamin D(2) analog (1,24(OH)(2)D(2)) on TNFalpha expression in macrophages. We also found an inhibitory effect in the physiological concentration (10(-10)M) of 1,25(OH)(2)D(3) which was dose-dependent. This down-regulation, caused by the decrease in NFkappaB activity by 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2), was demonstrated in P388D1 cells transfected with NFkappaB reporter gene (p NFkappaB-Luc) and by EMSA. In our present study we investigated the processes leading to reduced NFkappaB activity on P388D1 cells. A decrease in nuclei NFkappaB-p65 and an increase in cytosolic NFkappaB-p65, were measured, while no changes in total NFkappaB-p65 mRNA and protein levels were observed. Simultaneously, a significant increase in both mRNA and protein levels of the NFkappaB-cytosolic inhibitor, IkappaBalpha, were determined. The half-life of IkappaBalpha-mRNA increased, with a parallel decrease in the phosphorylation of its protein, as the first step of ubiquitinization and degradation. The present results demonstrate that 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2) inhibit TNFalpha expression in macrophages, by increasing IkappaBalpha and decreasing NFkappaB activity. Since NFkappaB is a major transcription factor for TNFalpha and other inflammatory mediators, these findings suggest that 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2) may be used therapeutically as anti-inflammatory agents.


Assuntos
Calcitriol/farmacologia , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Ergocalciferóis/farmacologia , Regulação da Expressão Gênica , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Fosforilação , Transporte Proteico , RNA Mensageiro/genética
14.
Nephrol Dial Transplant ; 21(4): 889-97, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16455676

RESUMO

BACKGROUND: In a previous study we demonstrated the inhibitory effect of 1,25-dihydroxyvitamin D (1,25(OH)(2)D(3)) and its less calcaemic analog 1,24(OH)(2)D(2) on the production of tumour necrosis factor alpha (TNFalpha) by human peritoneal macrophages. The aim of the present study is to examine whether this vitamin D inhibition of TNFalpha is mediated by its major transcription factor, nuclear factor-kappaB (NFkappaB). METHODS: Murine macrophage cells (P388D1) were incubated with 10(-7) M 1,25(OH)(2)D(3) or 1,24(OH)(2)D(2) and then stimulated with lipopolysaccharide. NFkappaB activity was assayed using a reporter gene and by electrophoretic mobility shift assay (EMSA). In addition, we evaluated mRNA and protein levels of NFkappaB-p65 and of IkappaBalpha, a potent NFkappaB inhibitor, and phosphorylated IkappaBalpha. RESULTS: Both 1,25(OH)(2)D(3) and 1,24(OH)(2)D(2) induced a 60% reduction of TNFalpha secretion. By using a reporter gene and EMSA we found that vitamin D markedly reduced NFkappaB activity. 1,25(OH)(2)D(3) or 1,24(OH)(2)D(2) decreased NFkappaB-p65 levels in the nucleus and increased NFkappaB-p65 levels in the cytosol; no changes were observed in the total levels of NFkappaB-p65 protein and mRNA. Concurrently, vitamin D induced a significant increase in mRNA and protein levels of IkappaBalpha (approximately 6.5- and 4.5-fold, respectively). Elevated levels of IkappaBalpha can be explained by the vitamin D-induced prolongation of IkappaBalpha-mRNA half-life from 110 to 190 min and by the decrease in IkappaBalpha phosphorylation. CONCLUSIONS: Vitamin D up-regulates IkappaBalpha levels by increasing mRNA stability and decreasing IkappaBalpha phosphorylation. The increase in IkappaBalpha levels reduces nuclear translocation of NFkappaB and thereby downgrades its activity. Since NFkappaB is a major transcription factor of inflammatory mediators, these findings suggest that the less-calcaemic analog, 1,24(OH)(2)D(2) may be effective as an anti-inflammatory therapeutic agent.


Assuntos
Proteínas I-kappa B/metabolismo , Macrófagos/efeitos dos fármacos , NF-kappa B/metabolismo , Vitamina D/farmacologia , Animais , Núcleo Celular , Células Cultivadas , Proteínas I-kappa B/genética , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Inibidor de NF-kappaB alfa , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , Fosforilação , Transporte Proteico , Estabilidade de RNA , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Fator de Necrose Tumoral alfa/metabolismo
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