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1.
Am J Clin Nutr ; 107(5): 725-733, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29722846

RESUMO

Background: Vitamin D deficiency is common in children with severe acute malnutrition, in whom it is associated with severe wasting. Ready-to-use therapeutic food (the standard treatment) contains modest amounts of vitamin D that do not reliably correct deficiency. Objective: The aim of this study was to determine whether high-dose oral vitamin D3 enhances weight gain and development in children with uncomplicated severe acute malnutrition. Design: We conducted a randomized placebo-controlled trial of high-dose vitamin D3 supplementation in children aged 6-58 mo with uncomplicated severe acute malnutrition in Pakistan. Participants were randomly assigned to receive 2 oral doses of 200,000 IU vitamin D3 or placebo at 2 and 4 wk after starting ready-to-use therapeutic food. The primary outcome was the proportion of participants gaining >15% of baseline weight at 8 wk after starting ready-to-use therapeutic food (the end of the study). Secondary outcomes were mean weight-for-height or -length z score and the proportion of participants with delayed development at the end of the study (assessed with the Denver Development Screening Tool II), adjusted for baseline values. Results: Of the 194 randomly assigned children who started the study, 185 completed the follow-up and were included in the analysis (93 assigned to intervention, 92 to control). High-dose vitamin D3 did not influence the proportion of children gaining >15% of baseline weight at the end of the study (RR: 1.04; 95% CI: 0.94,1.15, P = 0.47), but it did increase the weight-for-height or -length z score (adjusted mean difference: 1.07; 95% CI: 0.49,1.65, P < 0.001) and reduce the proportion of participants with delayed global development [adjusted RR (aRR): 0.49; 95% CI: 0.31, 0.77, P = 0.002], delayed gross motor development (aRR: 0.29; 95% CI: 0.13, 0.64, P = 0.002), delayed fine motor development (aRR: 0.59; 95% CI: 0.38, 0.91, P = 0.018), and delayed language development (aRR: 0.57; 95% CI: 0.34, 0.96, P = 0.036). Conclusions: High-dose vitamin D3 improved the mean weight-for-height or -length z score and developmental indexes in children receiving standard therapy for uncomplicated severe acute malnutrition in Pakistan. This trial was registered at clinicaltrials.gov as NCT03170479.


Assuntos
Transtornos da Nutrição Infantil/tratamento farmacológico , Colecalciferol/administração & dosagem , Transtornos da Nutrição do Lactente/tratamento farmacológico , Pré-Escolar , Colecalciferol/farmacologia , Dieta , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Lactente , Masculino , Vitaminas/administração & dosagem , Vitaminas/farmacologia
2.
J Steroid Biochem Mol Biol ; 175: 138-145, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28161533

RESUMO

Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease (COPD), yet a comprehensive analysis of environmental and genetic determinants of serum 25-hydroxyvitamin D (25[OH]D) concentration in patients with this condition is lacking. We conducted a multi-centre cross-sectional study in 278 COPD patients aged 41-92 years in London, UK. Details of potential environmental determinants of vitamin D status and COPD symptom control and severity were collected by questionnaire, and blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction. All participants performed spirometry and underwent measurement of weight and height. Quadriceps muscle strength (QS) was measured in 134 participants, and sputum induction with enumeration of lower airway eosinophil and neutrophil counts was performed for 44 participants. Thirty-seven single nucleotide polymorphisms (SNP) in 11 genes in the vitamin D pathway (DBP, DHCR7, CYP2R1, CYP27B1, CYP24A1, CYP27A1, CYP3A4, LRP2, CUBN, RXRA, and VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration and to determine whether vitamin D status or genetic factors independently associated with % predicted forced expiratory volume in one second (FEV1), % predicted forced vital capacity (FVC), the ratio of FEV1 to FVC (FEV1:FVC), daily inhaled corticosteroid (ICS) dose, respiratory quality of life (QoL), QS, and the percentage of eosinophils and neutrophils in induced sputum. Mean serum 25(OH)D concentration was 45.4nmol/L (SD 25.3); 171/278 (61.5%) participants were vitamin D deficient (serum 25[OH]D concentration <50nmol/L). Lower vitamin D status was independently associated with higher body mass index (P=0.001), lower socio-economic position (P=0.037), lack of vitamin D supplement consumption (P<0.001), sampling in Winter or Spring (P for trend=0.006) and lack of a recent sunny holiday (P=0.002). Vitamin D deficiency associated with reduced % predicted FEV1 (P for trend=0.060) and % predicted FVC (P for trend=0.003), but it did not associate with FEV1:FVC, ICS dose, QoL, QS, or the percentage of eosinophils or neutrophils in induced sputum. After correction for multiple comparisons testing, genetic variation in the vitamin D pathway was not found to associate with serum 25(OH)D concentration or clinical correlates of COPD severity. Vitamin D deficiency was common in this group of COPD patients in the UK, and it associated independently with reduced % predicted FEV1 and FVC. However, genetic variation in the vitamin D pathway was not associated with vitamin D status or severity of COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos Transversais , Sistema Enzimático do Citocromo P-450/sangue , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Ligação a DNA/sangue , Proteínas de Ligação a DNA/genética , Eosinófilos/metabolismo , Eosinófilos/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Londres/epidemiologia , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/sangue , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Neutrófilos/patologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/sangue , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Prevalência , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/genética , Grupos Raciais , Receptores de Calcitriol/sangue , Receptores de Calcitriol/genética , Receptores de Superfície Celular/sangue , Receptores de Superfície Celular/genética , Testes de Função Respiratória , Índice de Gravidade de Doença , Fatores de Transcrição/sangue , Fatores de Transcrição/genética , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/genética
3.
J Steroid Biochem Mol Biol ; 175: 88-96, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27825992

RESUMO

Vitamin D deficiency is common in children with asthma, and it associates with poor asthma control, reduced forced expiratory volume in one second (FEV1) and increased requirement for inhaled corticosteroids (ICS). Cross-sectional studies investigating the prevalence, determinants and clinical correlates of vitamin D deficiency in adults with asthma are lacking. We conducted a multi-centre cross-sectional study in 297 adults with a medical record diagnosis of ICS-treated asthma living in London, UK. Details of potential environmental determinants of vitamin D status, asthma control and medication use were collected by questionnaire; blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction, and participants underwent measurement of weight, height and fractional exhaled nitric oxide concentration (FeNO), spirometry and sputum induction for determination of lower airway eosinophil counts (n=35 sub-group). Thirty-five single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DBP, DHCR7, RXRA, CYP2R1, CYP27B1, CYP24A1, CYP3A4 CYP27A1, LRP2, CUBN, VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration, and to determine whether vitamin D status was independently associated with Asthma Control Test (ACT) score, ICS dose, FeNO, forced vital capacity (FVC), FEV1 or lower airway eosinophilia. Mean serum 25(OH)D concentration was 50.6nmol/L (SD 24.9); 162/297 (54.5%) participants were vitamin D deficient (serum 25(OH)D concentration <50nmol/L). Lower vitamin D status was associated with higher body mass index (P=0.014), non-White ethnicity (P=0.036), unemployment (P for trend=0.012), lack of vitamin D supplement use (P<0.001), sampling in Winter or Spring (P for trend <0.001) and lack of a recent sunny holiday abroad (P=0.030), but not with potential genetic determinants. Vitamin D status was not found to associate with any marker of asthma control investigated. Vitamin D deficiency is common among UK adults with ICS-treated asthma, and classical environmental determinants of serum 25(OH)D operate in this population. However, in contrast to studies conducted in children, we found no association between vitamin D status and markers of asthma severity or control.


Assuntos
Asma/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Administração por Inalação , Adolescente , Corticosteroides/uso terapêutico , Adulto , Idoso , Antiasmáticos/uso terapêutico , Asma/sangue , Asma/complicações , Asma/tratamento farmacológico , Índice de Massa Corporal , Estudos Transversais , Sistema Enzimático do Citocromo P-450/sangue , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Ligação a DNA/sangue , Proteínas de Ligação a DNA/genética , Eosinófilos/metabolismo , Eosinófilos/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Londres/epidemiologia , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/sangue , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Masculino , Pessoa de Meia-Idade , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/sangue , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Grupos Raciais , Receptores de Calcitriol/sangue , Receptores de Calcitriol/genética , Receptores de Superfície Celular/sangue , Receptores de Superfície Celular/genética , Testes de Função Respiratória , Índice de Gravidade de Doença , Fatores de Transcrição/sangue , Fatores de Transcrição/genética , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico
4.
J Steroid Biochem Mol Biol ; 164: 30-35, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26776442

RESUMO

Despite the high prevalence of vitamin D deficiency among older adults in the UK, studies investigating the determinants of vitamin D status in this group are lacking. We conducted a cross-sectional study in 222 older adults living in sheltered accommodation in London, UK, who were screened for participation in a clinical trial of vitamin D supplementation for the prevention of acute respiratory infection. Details of potential demographic and lifestyle determinants of vitamin D status were collected by questionnaire and blood samples were taken for analysis of serum 25-hydroxyvitamin D (25[OH]D) concentration and DNA extraction. Fifteen single nucleotide polymorphisms (SNP) in 6 genes (DBP, DHCR7, CYP2R1, CYP27B1, CYP24A1, VDR) previously reported to associate with circulating 25(OH)D concentration were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration. Mean serum 25(OH)D concentration was 42.7nmol/L (SD 22.0); 144/222 (64.9%) participants had serum 25(OH)D concentrations <50nmol/L. The following factors were independently associated with lower serum 25(OH)D concentration: non-white ethnicity (-8.6nmol/L, 95% CI -14.9 to -2.3, P=0.008); lack of vitamin D supplement consumption (-17.1nmol/L, 95% CI -23.3 to -10.9, P<0.001) vs. taking a daily supplement; sampling in Q1/January-March (-12.2nmol/L, 95% CI -21.5 to -2.9, P=0.01), and sampling in Q4/October-December (-10.3nmol/L, 95% CI -20.2 to -0.4, P=0.04) vs. sampling in Q3/July-September. None of the 15 SNP investigated independently associated with serum 25(OH)D concentration after correcting for multiple comparisons. In conclusion, vitamin D deficiency was highly prevalent among the older adults in this study; non-White ethnicity, lack of vitamin D supplement consumption and sampling in winter and spring independently associated with lower vitamin D status.


Assuntos
Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/genética , Vitamina D/análogos & derivados , Vitamina D/genética , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Colestanotriol 26-Mono-Oxigenase/genética , Ensaios Clínicos como Assunto , Estudos de Coortes , Estudos Transversais , Família 2 do Citocromo P450/genética , Proteínas de Ligação a DNA/genética , Dieta , Suplementos Nutricionais , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Receptores de Calcitriol/genética , Estações do Ano , Fatores de Transcrição/genética , Vitamina D/sangue , Vitamina D/uso terapêutico , Deficiência de Vitamina D/epidemiologia , Vitamina D3 24-Hidroxilase/genética
5.
Thorax ; 70(10): 953-60, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26063508

RESUMO

RATIONALE: Low-dose vitamin D supplementation is already recommended in older adults for prevention of fractures and falls, but clinical trials investigating whether higher doses could provide additional protection against acute respiratory infection (ARI) are lacking. OBJECTIVE: To conduct a clinical trial of high-dose versus low-dose vitamin D3 supplementation for ARI prevention in residents of sheltered-accommodation housing blocks ('schemes') and their carers in London, UK. MEASUREMENTS AND METHODS: Fifty-four schemes (137 individual participants) were allocated to the active intervention (vitamin D3 2.4 mg once every 2 months +10 µg daily for residents, 3 mg once every 2 months for carers), and 54 schemes with 103 participants were allocated to control (placebo once every 2 months +vitamin D3 10 µg daily for residents, placebo once every 2 months for carers) for 1 year. Primary outcome was time to first ARI; secondary outcomes included time to first upper/lower respiratory infection (URI/LRI, analysed separately), and symptom duration. MAIN RESULTS: Inadequate vitamin D status was common at baseline: 220/240 (92%) participants had serum 25(OH)D concentration <75 nmol/L. The active intervention did not influence time to first ARI (adjusted HR (aHR) 1.18, 95% CI 0.80 to 1.74, p=0.42). When URI and LRI were analysed separately, allocation to the active intervention was associated with increased risk of URI (aHR 1.48, 95% CI 1.02 to 2.16, p=0.039) and increased duration of URI symptoms (median 7.0 vs 5.0 days for active vs control, adjusted ratio of geometric means 1.34, 95% CI 1.09 to 1.65, p=0.005), but not with altered risk or duration of LRI. CONCLUSIONS: Addition of intermittent bolus-dose vitamin D3 supplementation to a daily low-dose regimen did not influence risk of ARI in older adults and their carers, but was associated with increased risk and duration of URI. TRIAL REGISTRATION NUMBER: clinicaltrials.gov NCT01069874.


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Infecções Respiratórias/prevenção & controle , Vitaminas/uso terapêutico , Doença Aguda , Idoso , Cuidadores , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Casas de Saúde
6.
Thorax ; 70(5): 451-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25724847

RESUMO

RATIONALE: Asthma exacerbations are commonly precipitated by viral upper respiratory infections (URIs). Vitamin D insufficiency associates with susceptibility to URI in patients with asthma. Trials of vitamin D in adults with asthma with incidence of exacerbation and URI as primary outcome are lacking. OBJECTIVE: To conduct a randomised controlled trial of vitamin D3 supplementation for the prevention of asthma exacerbation and URI (coprimary outcomes). MEASUREMENTS AND METHODS: 250 adults with asthma in London, UK were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 (n=125) or placebo (n=125) over 1 year. Secondary outcomes included asthma control test and St George's Respiratory Questionnaire scores, fractional exhaled nitric oxide and concentrations of inflammatory markers in induced sputum. Subgroup analyses were performed to determine whether effects of supplementation were modified by baseline vitamin D status or genotype for 34 single nucleotide polymorphisms in 11 vitamin D pathway genes. MAIN RESULTS: 206/250 participants (82%) were vitamin D insufficient at baseline. Vitamin D3 did not influence time to first severe exacerbation (adjusted HR 1.02, 95% CI 0.69 to 1.53, p=0.91) or first URI (adjusted HR 0.87, 95% CI 0.64 to 1.16, p=0.34). No clinically important effect of vitamin D3 was seen on any of the secondary outcomes listed above. The influence of vitamin D3 on coprimary outcomes was not modified by baseline vitamin D status or genotype. CONCLUSIONS: Bolus-dose vitamin D3 supplementation did not influence time to exacerbation or URI in a population of adults with asthma with a high prevalence of baseline vitamin D insufficiency. TRIAL REGISTRATION NUMBER: NCT00978315 (ClinicalTrials.gov).


Assuntos
Asma/complicações , Asma/prevenção & controle , Colecalciferol/administração & dosagem , Suplementos Nutricionais , Infecções Respiratórias/prevenção & controle , Vitaminas/administração & dosagem , Adulto , Estudos de Coortes , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/epidemiologia , Fatores de Tempo
7.
J Allergy Clin Immunol ; 136(3): 628-637.e4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25772594

RESUMO

BACKGROUND: A small population of patients with severe asthma does not respond to glucocorticoids (steroid resistant [SR]). They have high morbidity, highlighting an urgent need for strategies to enhance glucocorticoid responsiveness. OBJECTIVE: We investigated the immunologic differences between steroid-sensitive (SS) and SR asthmatic patients and the effect on immunophenotype of oral calcitriol treatment because it has been previously shown to beneficially modulate the clinical response to glucocorticoids in patients with SR asthma. METHODS: CD8-depleted PBMCs were isolated from 12 patients with SS and 23 patients with SR asthma and cultured for 7 days with anti-CD3 and IL-2 with or without dexamethasone. Cytokine production was assessed in supernatants by using the Cytometric Bead Array. Patients with SR asthma were subsequently randomized to oral calcitriol or placebo therapy, and identical studies were repeated. RESULTS: Patients with SR asthma produced significantly increased IL-17A and IFN-γ levels compared with those in patients with SS asthma, although it was evident that cells from individual patients might overproduce one or the other of these cytokines. Production of IL-17A was inversely and production of IL-13 was positively associated with the clinical response to prednisolone. Oral calcitriol, compared with placebo, therapy of the patients with SR asthma significantly improved dexamethasone-induced IL-10 production in vitro while suppressing dexamethasone-induced IL-17A production. This effect mirrored the previously demonstrated improvement in clinical response to oral glucocorticoids in calcitriol-treated patients with SR asthma. CONCLUSIONS: IL-17A(high) and IFN-γ(high) immunophenotypes exist in patients with SR asthma. These data identify immunologic pathways that likely underpin the beneficial clinical effects of calcitriol in patients with SR asthma by directing the SR cytokine profile toward a more SS immune phenotype, suggesting strategies for identifying vitamin D responder immunophenotypes.


Assuntos
Asma/tratamento farmacológico , Calcitriol/uso terapêutico , Fatores Imunológicos/uso terapêutico , Interferon gama/biossíntese , Interleucina-17/biossíntese , Leucócitos Mononucleares/efeitos dos fármacos , Prednisolona/uso terapêutico , Corticosteroides/farmacologia , Adulto , Asma/imunologia , Asma/patologia , Complexo CD3/farmacologia , Dexametasona/farmacologia , Resistência a Medicamentos , Feminino , Humanos , Imunofenotipagem , Interferon gama/imunologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Interleucina-17/imunologia , Interleucina-2/farmacologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Índice de Gravidade de Doença
8.
Lancet Respir Med ; 3(2): 120-130, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25476069

RESUMO

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) often have vitamin D deficiency, which is associated with increased susceptibility to upper respiratory infection-a major precipitant of exacerbation. Multicentre trials of vitamin D supplementation for prevention of exacerbation and upper respiratory infection in patients with COPD are lacking. We therefore investigated whether vitamin D3 (colecalciferol) supplementation would reduce the incidence of moderate or severe COPD exacerbations and upper respiratory infections. METHODS: We did a randomised, double-blind, placebo-controlled trial of vitamin D3 supplementation in adults with COPD in 60 general practices and four Acute National Health Service Trust clinics in London, UK. Patients were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 or placebo over 1 year in a 1:1 ratio using computer-generated permuted block randomisation. Participants and study staff were masked to treatment assignment. Coprimary outcomes were time to first moderate or severe exacerbation and first upper respiratory infection. Analysis was by intention to treat. A prespecified subgroup analysis was done to assess whether effects of the intervention on the coprimary outcomes were modified by baseline vitamin D status. This trial is registered with ClinicalTrials.gov, number NCT00977873. FINDINGS: 240 patients were randomly allocated to the vitamin D3 group (n=122) and placebo group (n=118). Vitamin D3 compared with placebo did not affect time to first moderate or severe exacerbation (adjusted hazard ratio 0·86, 95% CI 0·60-1·24, p=0·42) or time to first upper respiratory infection (0·95, 0·69-1·31, p=0·75). Prespecified subgroup analysis showed that vitamin D3 was protective against moderate or severe exacerbation in participants with baseline serum 25-hydroxyvitamin D concentrations of less than 50 nmol/L (0·57, 0·35-0·92, p=0·021), but not in those with baseline 25-hydroxyvitamin D levels of at least 50 nmol/L (1·45, 0·81-2·62, p=0·21; p=0·021 for interaction between allocation and baseline serum 25-hydroxyvitamin D status). Baseline vitamin D status did not modify the effect of the intervention on risk of upper respiratory infection (pinteraction=0·41). INTERPRETATION: Vitamin D3 supplementation protected against moderate or severe exacerbation, but not upper respiratory infection, in patients with COPD with baseline 25-hydroxyvitamin D levels of less than 50 nmol/L. Our findings suggest that correction of vitamin D deficiency in patients with COPD reduces the risk of moderate or severe exacerbation. FUNDING: UK National Institute for Health Research.


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Doença Pulmonar Obstrutiva Crônica/dietoterapia , Vitaminas/uso terapêutico , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/complicações , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/dietoterapia
10.
BMC Public Health ; 13: 999, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24152375

RESUMO

BACKGROUND: The global prevalence of type 2 diabetes is increasing. Effective strategies to address this public health challenge are currently lacking. A number of epidemiological studies have reported associations between low concentrations of 25-hydroxy vitamin D and the incidence of diabetes, but a causal link has not been established. We investigate the effect of vitamin D supplementation on the metabolic status of individuals at increased risk of developing type 2 diabetes. METHODS/DESIGN: In a randomised double-blind placebo-controlled trial individuals identified as having a high risk of type 2 diabetes (non-diabetic hyperglycaemia or positive diabetes risk score) are randomised into one of three groups and given 4 doses of either placebo, or 100,000 IU Vitamin D2 (ergocalciferol) or 100,000 IU Vitamin D3 (cholecalciferol) at monthly intervals. The primary outcome measure is the change in glycated haemoglobin level between baseline and 4 months. Secondary outcome measures include blood pressure, lipid levels, apolipoproteins, highly sensitive C-reactive protein, parathyroid hormone (PTH) and safety of supplementation. and C-reactive protein. The trial is being conducted at two sites (London and Cambridge, U.K.) and a total of 342 participants are being recruited. DISCUSSION: Trial data examining whether supplementation of vitamin D improves glycaemic status and other metabolic parameters in people at risk of developing type 2 diabetes are sparse. This trial will evaluate the causal role of vitamin D in hyperglycaemia and risk of type 2 diabetes. Specific features of this trial include recruitment of participants from different ethnic groups, investigation of the relative effectiveness and safety of vitamin D2 and D3 and an evidence based approach to determination of the dose of supplementation. TRIAL REGISTRATION: EudraCT2009-011264-11; ISRCTN86515510.


Assuntos
Colecalciferol/uso terapêutico , Diabetes Mellitus Tipo 2/prevenção & controle , Suplementos Nutricionais/estatística & dados numéricos , Ergocalciferóis/uso terapêutico , Hiperglicemia/tratamento farmacológico , Adulto , Idoso , Glicemia/efeitos dos fármacos , Proteína C-Reativa/efeitos dos fármacos , Colecalciferol/administração & dosagem , Colecalciferol/sangue , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Ergocalciferóis/administração & dosagem , Ergocalciferóis/sangue , Feminino , Seguimentos , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Hiperglicemia/sangue , Londres , Masculino , Pessoa de Meia-Idade , Risco , Resultado do Tratamento , Vitaminas/administração & dosagem , Vitaminas/sangue , Vitaminas/uso terapêutico
11.
PLoS Pathog ; 9(7): e1003468, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23853590

RESUMO

Distinct phylogenetic lineages of Mycobacterium tuberculosis (MTB) cause disease in patients of particular genetic ancestry, and elicit different patterns of cytokine and chemokine secretion when cultured with human macrophages in vitro. Circulating and antigen-stimulated concentrations of these inflammatory mediators might therefore be expected to vary significantly between tuberculosis patients of different ethnic origin. Studies to characterise such variation, and to determine whether it relates to host or bacillary factors, have not been conducted. We therefore compared circulating and antigen-stimulated concentrations of 43 inflammatory mediators and 14 haematological parameters (inflammatory profile) in 45 pulmonary tuberculosis patients of African ancestry vs. 83 patients of Eurasian ancestry in London, UK, and investigated the influence of bacillary and host genotype on these profiles. Despite having similar demographic and clinical characteristics, patients of differing ancestry exhibited distinct inflammatory profiles at presentation: those of African ancestry had lower neutrophil counts, lower serum concentrations of CCL2, CCL11 and vitamin D binding protein (DBP) but higher serum CCL5 concentrations and higher antigen-stimulated IL-1 receptor antagonist and IL-12 secretion. These differences associated with ethnic variation in host DBP genotype, but not with ethnic variation in MTB strain. Ethnic differences in inflammatory profile became more marked following initiation of antimicrobial therapy, and immunological correlates of speed of elimination of MTB from the sputum differed between patients of African vs. Eurasian ancestry. Our study demonstrates a hitherto unappreciated degree of ethnic heterogeneity in inflammatory profile in tuberculosis patients that associates primarily with ethnic variation in host, rather than bacillary, genotype. Candidate immunodiagnostics and immunological biomarkers of response to antimicrobial therapy should be derived and validated in tuberculosis patients of different ethnic origin.


Assuntos
Interações Hospedeiro-Patógeno , Mediadores da Inflamação/sangue , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/imunologia , Adulto , Antibióticos Antituberculose/uso terapêutico , Antígenos de Bactérias/metabolismo , Povo Asiático , Carga Bacteriana/efeitos dos fármacos , População Negra , Células Sanguíneas/imunologia , Células Sanguíneas/metabolismo , Células Cultivadas , Feminino , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Isoniazida/uso terapêutico , Londres , Masculino , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Escarro/efeitos dos fármacos , Escarro/microbiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/etnologia , Tuberculose Pulmonar/virologia , População Branca , Adulto Jovem
12.
J Allergy Clin Immunol ; 132(2): 297-304.e3, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23683514

RESUMO

BACKGROUND: TH17 cells are proposed to play a role in the pathology of asthma, including steroid-resistant (SR) disease. We previously identified a steroid-enhancing function of vitamin D in patients with SR asthma in restoring the impaired response to steroids for production of the anti-inflammatory cytokine IL-10. OBJECTIVE: We sought to investigate the production of the TH17-associated cytokines IL-17A and IL-22 in culture in patients with moderate-to-severe asthma defined on the basis of their clinical response to steroids and the susceptibility of this response to inhibition by steroids and the active form of vitamin D, 1α,25-dihydroxyvitamin D3 (1,25[OH]2D3). METHODS: PBMCs were stimulated in culture with or without dexamethasone and 1,25(OH)2D3. A cytometric bead array, ELISA, and intracellular cytokine staining were used to assess cytokine production. The role of CD39 in inhibition of the TH17 response was studied by using quantitative real-time PCR, flow cytometry, and addition of the antagonist POM-1 to culture. RESULTS: Asthmatic patients synthesized much higher levels of IL-17A and IL-22 than nonasthmatic control subjects, with patients with SR asthma expressing the highest levels of IL-17A. Glucocorticoids did not inhibit IL-17A cytokine expression in patients and enhanced production in cultures from control subjects. Treatment with 1,25(OH)2D3 with or without dexamethasone significantly reduced both IL-17A and IL-22 levels. An antagonist of the ectonucleotidase CD39 reversed 1,25(OH)2D3-mediated inhibition of the IL-17A response. CONCLUSION: Patients with severe asthma exhibit increased levels of TH17 cytokines, which are not inhibited by steroids. 1,25(OH)2D3 inhibits TH17 cytokine production in all patients studied, irrespective of their clinical responsiveness to steroids, identifying novel steroid-enhancing properties of vitamin D in asthmatic patients.


Assuntos
Asma/fisiopatologia , Glucocorticoides/uso terapêutico , Interleucina-17/biossíntese , Regulação para Cima , Vitamina D/análogos & derivados , Adulto , Asma/tratamento farmacológico , Asma/imunologia , Células Cultivadas , Resistência a Medicamentos , Feminino , Glucocorticoides/farmacologia , Humanos , Interleucina-10/biossíntese , Interleucina-10/genética , Interleucina-17/genética , Interleucinas/biossíntese , Interleucinas/genética , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Índice de Gravidade de Doença , Células Th17/imunologia , Células Th17/metabolismo , Vitamina D/farmacologia , Vitamina D/uso terapêutico , Interleucina 22
13.
J Bone Miner Res ; 28(6): 1301-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23281057

RESUMO

Animal models suggest a key role for dihydroxylated vitamin D metabolites in fracture healing, as evidenced by increases in serum concentration of 24R,25-dihydroxyvitamin D (24R,25[OH]2D) after long bone fracture. Human studies investigating the kinetics of serum concentrations of 24R,25[OH]2D, 1,25-dihydroxyvitamin D (1,25[OH]2D) and their parent metabolite 25-hydroxyvitamin D (25[OH]D) are lacking. We, therefore, conducted a longitudinal study to determine whether total, free, or bioavailable concentrations of these vitamin D metabolites fluctuate in humans after long bone fracture. Twenty-eight patients with cross-shaft (diaphyseal) long bone fracture presenting to an emergency department in London, UK, were studied. Serum concentrations of 25(OH)D, 24R,25(OH)2D, 1,25(OH)2D, vitamin D binding protein, albumin, and calcium were determined within 48 hours of fracture and again at 1 and 6 weeks postfracture. Concentrations of free and bioavailable vitamin D metabolites were calculated using standard equations. No changes in mean serum concentrations of 25(OH)D or 24R,25(OH)2D were seen at either follow-up time point versus baseline. In contrast, mean serum 1,25(OH)2 D concentration declined by 21% over the course of the study, from 68.5 pmol/L at baseline to 54.1 pmol/L at 6 weeks (p < 0.05). This decline was associated with an increase in mean serum corrected calcium concentration, from 2.32 mmol/L at baseline to 2.40 mmol/L at 1 week (p < 0.001) that was maintained at 6 weeks. No changes in free or bioavailable concentrations of any vitamin D metabolite investigated were seen over the course of the study. We conclude that serum 1,25(OH)2D concentration declines after long bone fracture in humans but that the serum 24R,25(OH)2D concentration does not fluctuate. The latter finding contrasts with those of animal models reporting increases in serum 24R,25(OH)2D concentration after long bone fracture.


Assuntos
24,25-Di-Hidroxivitamina D 3/sangue , Calcitriol/sangue , Fraturas Ósseas/sangue , Adulto , Idoso , Albuminas/metabolismo , Serviço Hospitalar de Emergência , Feminino , Seguimentos , Fraturas Ósseas/patologia , Fraturas Ósseas/terapia , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Proteína de Ligação a Vitamina D/sangue
14.
Proc Natl Acad Sci U S A ; 109(38): 15449-54, 2012 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-22949664

RESUMO

Calcidiol, the major circulating metabolite of vitamin D, supports induction of pleiotropic antimicrobial responses in vitro. Vitamin D supplementation elevates circulating calcidiol concentrations, and thus has a potential role in the prevention and treatment of infection. The immunomodulatory effects of administering vitamin D to humans with an infectious disease have not previously been reported. To characterize these effects, we conducted a detailed longitudinal study of circulating and antigen-stimulated immune responses in ninety-five patients receiving antimicrobial therapy for pulmonary tuberculosis who were randomized to receive adjunctive high-dose vitamin D or placebo in a clinical trial, and who fulfilled criteria for per-protocol analysis. Vitamin D supplementation accelerated sputum smear conversion and enhanced treatment-induced resolution of lymphopaenia, monocytosis, hypercytokinaemia, and hyperchemokinaemia. Administration of vitamin D also suppressed antigen-stimulated proinflammatory cytokine responses, but attenuated the suppressive effect of antimicrobial therapy on antigen-stimulated secretion of IL-4, CC chemokine ligand 5, and IFN-α. We demonstrate a previously unappreciated role for vitamin D supplementation in accelerating resolution of inflammatory responses during tuberculosis treatment. Our findings suggest a potential role for adjunctive vitamin D supplementation in the treatment of pulmonary infections to accelerate resolution of inflammatory responses associated with increased risk of mortality.


Assuntos
Tuberculose/imunologia , Vitamina D/metabolismo , Adulto , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antituberculosos/farmacologia , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Sistema Imunitário , Inflamação , Cinética , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Análise de Regressão , Risco , Esteroides/química , Fatores de Tempo , Tuberculose/terapia , Vitamina D/uso terapêutico
16.
Proc Natl Acad Sci U S A ; 108(47): 19013-7, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22025704

RESUMO

Vitamin D deficiency is associated with susceptibility to tuberculosis (TB) in HIV-uninfected people in Europe, but it is not known whether such an association exists among HIV-infected people in subtropical Africa. We conducted a cross-sectional study to determine whether vitamin D deficiency was associated with susceptibility to active TB in HIV-uninfected (n = 196) and HIV-infected (n = 174) black Africans in Cape Town, South Africa. We also investigated whether there was evidence of seasonal variation in vitamin D status and TB notifications in this setting over an 8-y period. Vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] <50 nmol/L) was present in 232 (62.7%) of 370 participants and was associated with active TB in both HIV-uninfected (odds ratio = 5.2, 95% confidence interval: 2.8-9.7; P < 0.001) and HIV-infected (odds ratio = 5.6, 95% confidence interval: 2.7-11.6; P < 0.001) people. Vitamin D status varied according to season: The mean serum 25(OH)D concentration was highest in January through March and lowest in July through September (56.8 vs. 30.7 nmol/L, respectively; P < 0.001). Reciprocal seasonal variation in TB notifications was observed: The mean number of TB notifications per quarter for Cape Town in 2003 to 2010 was lowest in April through June and highest in October through December (4,222 vs. 5,080; P < 0.001). Vitamin D deficiency is highly prevalent among black Africans in Cape Town and is associated with susceptibility to active TB both in the presence and absence of HIV infection. Reciprocal seasonal variation in serum 25(OH)D concentration and TB notifications suggests that seasonal variations in vitamin D status and TB incidence in this setting are causally related.


Assuntos
Infecções por HIV/epidemiologia , Estações do Ano , Tuberculose/epidemiologia , Deficiência de Vitamina D/epidemiologia , Análise de Variância , Estudos Transversais , Infecções por HIV/complicações , Humanos , Razão de Chances , África do Sul/epidemiologia , Estatísticas não Paramétricas , Tuberculose/complicações , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/complicações
17.
Lancet ; 377(9761): 242-50, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21215445

RESUMO

BACKGROUND: Vitamin D was used to treat tuberculosis in the pre-antibiotic era, and its metabolites induce antimycobacterial immunity in vitro. Clinical trials investigating the effect of adjunctive vitamin D on sputum culture conversion are absent. METHODS: We undertook a multicentre randomised controlled trial of adjunctive vitamin D in adults with sputum smear-positive pulmonary tuberculosis in London, UK. 146 patients were allocated to receive 2·5 mg vitamin D(3) or placebo at baseline and 14, 28, and 42 days after starting standard tuberculosis treatment. The primary endpoint was time from initiation of antimicrobial treatment to sputum culture conversion. Patients were genotyped for TaqI and FokI polymorphisms of the vitamin D receptor, and interaction analyses were done to assess the influence of the vitamin D receptor genotype on response to vitamin D(3). This trial is registered with ClinicalTrials.gov number NCT00419068. FINDINGS: 126 patients were included in the primary efficacy analysis (62 assigned to intervention, 64 assigned to placebo). Median time to sputum culture conversion was 36·0 days in the intervention group and 43·5 days in the placebo group (adjusted hazard ratio 1·39, 95% CI 0·90-2·16; p=0.14). TaqI genotype modified the effect of vitamin D supplementation on time to sputum culture conversion (p(interaction)=0·03), with enhanced response seen only in patients with the tt genotype (8·09, 95% CI 1·36-48·01; p=0·02). FokI genotype did not modify the effect of vitamin D supplementation (p(interaction)=0·85). Mean serum 25-hydroxyvitamin D concentration at 56 days was 101·4 nmol/L in the intervention group and 22·8 nmol/L in the placebo group (95% CI for difference 68·6-88·2; p<0·0001). INTERPRETATION: Administration of four doses of 2·5 mg vitamin D(3) increased serum 25-hydroxyvitamin D concentrations in patients receiving intensive-phase treatment for pulmonary tuberculosis. Vitamin D did not significantly affect time to sputum culture conversion in the whole study population, but it did significantly hasten sputum culture conversion in participants with the tt genotype of the TaqI vitamin D receptor polymorphism. FUNDING: British Lung Foundation.


Assuntos
Antituberculosos/uso terapêutico , Colecalciferol/administração & dosagem , Tuberculose Pulmonar/tratamento farmacológico , Vitaminas/administração & dosagem , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Polimorfismo Genético , Receptores de Calcitriol/genética , Escarro/microbiologia , Taq Polimerase/genética , Adulto Jovem
18.
J Emerg Med ; 38(4): 463-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-18993019

RESUMO

BACKGROUND: Although salivary-type hyperamylasemia is known to occur with ovarian pathologies such as salpingitis and adenocarcinoma, pancreatic-type hyperamylasemia and hyperlipasemia are considered to be highly specific for pancreatitis. OBJECTIVES: To discuss the interpretation of hyperamylasemia in the context of acute abdominal pain, implications for management, and to review the literature relating to non-pancreatic causes of hyperamylasemia and hyperlipasemia. CASE REPORT: We present the case of a 25-year-old woman who presented with an acute abdomen and a markedly elevated pancreatic-type amylase and lipase in whom acute pancreatitis was suspected. Further investigations showed that the underlying pathology was actually a ruptured ovarian cyst causing massive intra-abdominal hemorrhage and necessitating emergency laparotomy. CONCLUSIONS: This case represents an initial report of pancreatic-type hyperamylasemia and hyperlipasemia occurring with ovarian pathology and hemoperitoneum. Although these derangements may have been secondary to peritoneal irritation, this case raises the possibility that ovarian tissue is able to secrete large amounts of pancreatic-type amylase and lipase in addition to salivary-type amylase. Clinicians should be aware that simultaneous elevations of both enzymes are not necessarily pathognomic of acute pancreatitis.


Assuntos
Hemorragia/diagnóstico por imagem , Hiperamilassemia/etiologia , Lipase/sangue , Cistos Ovarianos/complicações , Cistos Ovarianos/diagnóstico por imagem , Pancreatite/diagnóstico , Abdome Agudo/etiologia , Adulto , Amilases/química , Diagnóstico Diferencial , Feminino , Hemorragia/etiologia , Humanos , Pancreatite/sangue , Radiografia , Ruptura Espontânea/complicações , Ruptura Espontânea/diagnóstico por imagem
19.
Immunology ; 127(4): 539-48, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19178594

RESUMO

Matrix metalloproteinases (MMP) can degrade all components of pulmonary extracellular matrix. Mycobacterium tuberculosis induces production of a number of these enzymes by human macrophages, and these are implicated in the pathogenesis of pulmonary cavitation in tuberculosis. The active metabolite of vitamin D, 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)], has previously been reported to inhibit secretion of MMP-9 in human monocytes (MN), but its influence on the secretion and gene expression of MMP and tissue inhibitors of MMP (TIMP) in M. tuberculosis-infected cells has not previously been investigated. We therefore determined the effects of 1alpha,25(OH)(2)D(3) on expression, secretion and activity of a number of MMP and TIMP in M. tuberculosis-infected human leucocytes; we also investigated the effect of 1alpha,25(OH)(2)D(3) on the secretion of interleukin-10 (IL-10) and prostaglandin E(2) (PGE(2)), both transcriptional regulators of MMP expression. We found that M. tuberculosis induced expression of MMP-1, MMP-7 and MMP-10 in MN and MMP-1 and MMP-10 in peripheral blood mononuclear cells (PBMC). 1alpha,25(OH)(2)D(3) significantly attenuated M. tuberculosis-induced increases in expression of MMP-7 and MMP-10, and suppressed secretion of MMP-7 by M. tuberculosis-infected PBMC. MMP-9 gene expression, secretion and activity were significantly inhibited by 1alpha,25(OH)(2)D(3) irrespective of infection. In contrast, the effects of 1alpha,25(OH)(2)D(3) on the expression of TIMP-1, TIMP-2 and TIMP-3 and secretion of TIMP-1 and TIMP-2 were small and variable. 1alpha,25(OH)(2)D(3) also induced secretion of IL-10 and PGE(2) from M. tuberculosis-infected PBMC. These findings represent a novel immunomodulatory role for 1alpha,25(OH)(2)D(3) in M. tuberculosis infection.


Assuntos
Inibidores de Metaloproteinases de Matriz , Inibidores de Proteases/farmacologia , Tuberculose/enzimologia , Vitamina D/análogos & derivados , Células Cultivadas , Dinoprostona/biossíntese , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-10/biossíntese , Interleucina-10/genética , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/microbiologia , Metaloproteinases da Matriz/biossíntese , Metaloproteinases da Matriz/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Inibidores Teciduais de Metaloproteinases/biossíntese , Inibidores Teciduais de Metaloproteinases/genética , Tuberculose/sangue , Vitamina D/farmacologia
20.
Chest ; 126(4): 1330-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15486400

RESUMO

It is well-recognized that atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) are raised in conditions with ventricular volume and pressure overload. In addition to this established role in left ventricular congestive cardiac failure, there is good evidence that BNP has a diagnostic role in right ventricular (RV) dysfunction and pulmonary arterial hypertension (PAH). For example, BNP levels can be used to differentiate between dyspneic patients with pure respiratory defects and those with RV dysfunction. Studies in patients with PAH have demonstrated significant correlations between BNP levels and mean pulmonary arterial pressure as well as pulmonary vascular resistance. Additionally, BNP has a prognostic role in patients with RV pressure overload and pulmonary hypertension, and it offers a noninvasive test that can be used to guide therapy in patients with PAH. However, although measured plasma proBNP levels are raised in conditions with RV overload, its biological significance is still not well-understood. In this article, we review the general physiologic and potential therapeutic role of natriuretic peptides in respiratory disease, RV dysfunction, and PAH. Furthermore, we assess the various clues toward natriuretic peptide action coming from laboratory studies. ANP and BNP knockout mice develop cardiac fibrosis and hypertrophy. Potentiation of the natriuretic pathway has been shown to reduce cardiac hypertrophy and PAH. This is likely to take place as a result of increased intracellular cyclic guanosine monophosphate levels and subsequent pulmonary vasorelaxant activity. In view of this evidence, there may be a rationale for the therapeutic use of recombinant BNP or neutral endopeptidase inhibitors under conditions of RV dysfunction and PAH.


Assuntos
Fator Natriurético Atrial/fisiologia , Hipertensão Pulmonar/fisiopatologia , Peptídeo Natriurético Encefálico/fisiologia , Disfunção Ventricular Direita/fisiopatologia , Animais , Biomarcadores/sangue , Cardiomegalia/diagnóstico , Fibrose , Ventrículos do Coração/patologia , Humanos , Hipertensão Pulmonar/diagnóstico , Disfunção Ventricular Direita/diagnóstico , Pressão Ventricular
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