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1.
Eye Contact Lens ; 47(1): 2-7, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32097181

RESUMO

PURPOSE: Omega-3 (n-3) fatty acid supplementation is used to treat systemic inflammatory diseases, but the role of n-3 in the pathophysiology and therapy of dry eye disease (DED) is not definitive. We evaluated the relationship of systemic n-3 levels with signs and symptoms at baseline in the Dry Eye Assessment and Management (DREAM) Study. METHODS: Blood samples from participants at baseline were analyzed for n-3 and n-6, measured as relative percentage by weight among all fatty acids in erythrocytes. Symptoms were evaluated using the Ocular Surface Disease Index. Signs including conjunctival staining, corneal staining, tear breakup time (TBUT), and Schirmer's test with anesthesia were also evaluated. RESULTS: There was no correlation between the systemic n-3 levels and DED symptoms. When the associations with signs of DED were assessed, lower DHA levels were associated with higher conjunctival staining, with mean scores of 3.31, 2.96, and 2.82 for low, medium, and high levels of DHA, respectively (linear trend P=0.007). None of the other signs were associated with DHA or the other measures of n-3. CONCLUSION: Previous studies have found varying results on the role of n-3 supplementation with the signs and symptoms of DED. Among patients with DED enrolled in the DREAM Study, lower systemic n-3 levels were not associated with worse symptoms and most signs of DED.


Assuntos
Síndromes do Olho Seco , Ácidos Graxos Ômega-3 , Túnica Conjuntiva , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/tratamento farmacológico , Humanos , Lágrimas
2.
Neurotherapeutics ; 16(4): 1167-1182, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077039

RESUMO

X-Adrenoleukodystrophy (X-ALD) and its adult-onset, most prevalent variant adrenomyeloneuropathy (AMN) are caused by mutations in the peroxisomal transporter of the very long-chain fatty acid ABCD1. AMN patients classically present spastic paraparesis that can progress over decades, and a satisfactory treatment is currently lacking. Oxidative stress is an early culprit in X-ALD pathogenesis. A combination of antioxidants halts the clinical progression and axonal damage in a murine model of AMN, providing a strong rationale for clinical translation. In this phase II pilot, open-label study, 13 subjects with AMN were administered a high dose of α-tocopherol, N-acetylcysteine, and α-lipoic acid in combination. The primary outcome was the validation of a set of biomarkers for monitoring the biological effects of this and future treatments. Functional clinical scales, the 6-minute walk test (6MWT), electrophysiological studies, and cerebral MRI served as secondary outcomes. Most biomarkers of oxidative damage and inflammation were normalized upon treatment, indicating an interlinked redox and inflammatory homeostasis. Two of the inflammatory markers, MCP1 and 15-HETE, were predictive of the response to treatment. We also observed a significant decrease in central motor conduction time, together with an improvement or stabilization of the 6MWT in 8/10 subjects. This study provides a series of biomarkers that are useful to monitor redox and pro-inflammatory target engagement in future trials, together with candidate biomarkers that may serve for patient stratification and disease progression, which merit replication in future clinical trials. Moreover, the clinical results suggest a positive signal for extending these studies to phase III randomized, placebo-controlled, longer-term trials with the actual identified dose. ClinicalTrials.gov Identifier: NCT01495260.


Assuntos
Adrenoleucodistrofia/sangue , Adrenoleucodistrofia/tratamento farmacológico , Antioxidantes/administração & dosagem , Quimiocina CCL2/sangue , Ácidos Hidroxieicosatetraenoicos/sangue , Adrenoleucodistrofia/diagnóstico por imagem , Adulto , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/fisiologia , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
3.
Ecol Appl ; 29(2): e01842, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30585672

RESUMO

Population-level adaptation to spatial variation in factors such as climate and soils is critical for climate-vulnerability assessments, restoration seeding, and other ecological applications in species management, and the underlying information is typically based on common-garden studies that are short duration. Here, we show >20 yr were required for adaptive differences to emerge among 13 populations of a widespread shrub (sagebrush, Artemisia tridentata ssp wyomingensis) collected from around the western United States and planted into common gardens. Additionally, >10 yr were required for greater survival of local populations, that is, local adaptation, to become evident. Variation in survival was best explained by the combination of populations' home ecoregion combined with grouping of minimum temperature and aridity. Additional reductions in survival were explained by ungrouped (i.e., continuous) measures of garden-to-population-origin separation in geographic distance (5% decrease in survival per 100 km increase in separation; R2  = 0.22) and especially in minimum temperature in younger plants (-4% per + °C difference, R2  = 0.56 vs. 0.29 in the 14th vs. 27th post-planting years, respectively). Longer-term common garden studies are needed. While we await them, uncertainty in adaptive variation resulting from short-term observations could be quantitatively estimated and reported with seed-transfer guidelines to reduce risks of introducing maladapted provenances in restoration.


Assuntos
Artemisia , Jardins , Adaptação Fisiológica , Clima , Mudança Climática
4.
Cancer Med ; 3(6): 1562-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25132681

RESUMO

Phytanic acid is a saturated branched-chain fatty acid found predominantly in red meat and dairy products, and may contribute to the elevated risks of prostate cancer associated with higher consumption of these foods. Pristanic acid is formed during peroxisomal oxidation of phytanic acid, and is the direct substrate of α-Methyl-CoA-Racemase (AMACR)--an enzyme that is consistently overexpressed in prostate tumors relative to benign tissue. We measured phytanic and pristanic acids as percentages of total fatty acids by gas chromatography-mass spectrometry in prediagnostic blood samples from 300 prostate cancer cases and 300 matched controls, all of whom were participants in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study supplementation trial and follow-up cohort. In addition to providing a fasting blood sample at baseline, all men completed extensive diet, lifestyle, and medical history questionnaires. Among controls, the strongest dietary correlates of serum phytanic and pristanic acids were saturated fat, dairy fat, and butter (r = 0.50 and 0.40, 0.46 and 0.38, and 0.40 and 0.37, respectively; all P-values <0.001). There was no association between serum phytanic acid and risk of total or aggressive prostate cancer in multivariate logistic regression models (for increasing quartiles, odds ratios (OR) and 95% confidence intervals (CI) for aggressive cancer were 1.0 (referent), 1.62 (0.97-2.68), 1.12 (0.66-1.90), and 1.14 (0.67-1.94), P(trend) = 0.87). Pristanic acid was strongly correlated with phytanic acid levels (r = 0.73, P < 0.0001), and was similarly unrelated to prostate cancer risk. Significant interactions between phytanic and pristanic acids and baseline circulating ß-carotene concentrations were noted in relation to total and aggressive disease among participants who did not receive ß-carotene supplements as part of the original ATBC intervention trial. In summary, we observed no overall association between serum phytanic and pristanic acid levels and prostate cancer risk. Findings indicating that the direction and magnitude of these associations depended upon serum levels of the antioxidant ß-carotene among men not taking ß-carotene supplements should be interpreted cautiously, as they are likely due to chance.


Assuntos
Biomarcadores Tumorais/sangue , Ácidos Graxos/sangue , Ácido Fitânico/sangue , Neoplasias da Próstata/sangue , Fumar/sangue , Idoso , Estudos de Casos e Controles , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco
5.
J Ocul Pharmacol Ther ; 29(9): 837-41, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23971620

RESUMO

PURPOSE: To evaluate pill counts and red blood cell (RBC) membrane fatty acid profiles as measures of compliance with oral omega3 polyunsaturated fatty acids (ω3 PUFAs) and to compare the two techniques. METHODS: Sixteen dry eye disease subjects were given oral ω3 PUFA or placebo for 3 months. Compliance was measured by pill counts and blood tests at baseline and 3 months. The Wilcoxon signed-rank tests and rank-sum tests were used to compare changes from baseline and the difference between the two groups; Spearman correlation coefficients were used to assess the relationship of pill counts to changes in blood FAs. RESULTS: Pill counts for the ω3 (n=7) and placebo (n=9) groups showed a mean consumption of 4.39 and 4.76 pills per day, respectively. In the ω3 group, the median change from baseline was +1.46% for eicosapentaenoic acid (EPA) (P=0.03), +1.49% for docosahexaenoic acid (DHA) (P=0.08), and -1.91% for arachidonic acids (AA) (P=0.02). In the placebo group, median changes in all measured FAs were small and not statistically significant. The difference in change in FA levels between the two groups was significantly greater for EPA (P=0.01) and AA (P=0.04). The correlations between pill counts and changes in EPA (r=0.36, P=0.43) and DHA (r=0.17, P=0.70) were not strong. CONCLUSIONS: RBC FA analysis can be used to measure compliance in the active group and also monitor the placebo group for nonstudy ω3 intake. Low correlation of pill counts with blood levels suggests that pill counts alone may be inaccurate and should be replaced or supplemented with objective measures.


Assuntos
Suplementos Nutricionais , Síndromes do Olho Seco/tratamento farmacológico , Ácidos Graxos Ômega-3/administração & dosagem , Adesão à Medicação , Administração Oral , Adulto , Idoso , Ácidos Araquidônicos/administração & dosagem , Ácidos Araquidônicos/sangue , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/sangue , Método Duplo-Cego , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/sangue , Membrana Eritrocítica/metabolismo , Ácidos Graxos Ômega-3/sangue , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas
6.
Mol Genet Metab ; 105(3): 416-20, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22197596

RESUMO

X-linked adrenoleukodystrophy (X-ALD) is a severe genetic disorder that affects the nervous system, and the adrenal cortex. Newborn screening for X-ALD has been proposed to allow improved diagnosis along with prospective monitoring and treatment for this severe disorder. Newborn dried whole blood spot (DBS) 26:0 lysophosphatidyl choline was validated as a diagnostic marker for X-ALD and other peroxisomal disorders of peroxisomal ß-oxidation. In this study, we developed a new one step extraction procedure that simultaneously extracts acyl carnitines and the lysophosphatidyl cholines from DBS. Further analysis of these metabolites has been performed by two different high throughput LC-MS/MS methods. The 26:0 lysophosphatidyl choline levels in this study were consistent with previously published values and discriminate between healthy and abnormal profiles. There is a very minor modification to the original acyl carnitine extraction procedure and our data indicates that there is no significant effect on acyl carnitine levels in DBS. Our new method potentially can be complementary to the current newborn screening panel. It successfully combines the existing method for acyl carnitine analysis and 26:0 lysophosphatidyl choline that can be applied for prospective X-ALD newborn screening.


Assuntos
Adrenoleucodistrofia/diagnóstico , Carnitina/análogos & derivados , Teste em Amostras de Sangue Seco , Lisofosfatidilcolinas/sangue , Triagem Neonatal/métodos , Adrenoleucodistrofia/sangue , Adrenoleucodistrofia/genética , Carnitina/sangue , Cromatografia Líquida/métodos , Humanos , Recém-Nascido , Espectrometria de Massas , Técnicas de Diagnóstico Molecular , Transtornos Peroxissômicos/diagnóstico , Transtornos Peroxissômicos/genética , Peroxissomos/genética , Peroxissomos/metabolismo
7.
Mol Genet Metab ; 99(4): 408-16, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20060764

RESUMO

Rhizomelic chondrodysplasia punctata type 1 is a peroxisome biogenesis disorder with the clinical features of rhizomelia, abnormal epiphyseal calcifications, congenital cataracts, and profound growth and developmental delays. It is a rare autosomal recessive disorder, caused by defects in the peroxisome receptor, PEX7. The pathology results from a deficiency of plasmalogens, a critical class of ether phospholipids whose functions are largely unknown. To study plasmalogens in an animal model, avoid early mortality and facilitate therapeutic investigations in this disease, we engineered a hypomorphic mouse model in which Pex7 transcript levels are reduced to less than 5% of wild type. These mice are born in expected ratios, are fertile and have a normal life span. However, they are petite and develop early cataracts. Further investigations showed delayed endochondral ossification and abnormalities in lens fibers. The biochemical features of reduced Pex7 function were reproduced in this model, including tissue plasmalogen deficiency, phytanic acid accumulation, reduced import of Pex7 ligands and consequent defects in plasmalogen biosynthesis and phytanic acid oxidation. Dietary supplementation with batyl alcohol, a plasmalogen precursor, recovered ether phospholipids in blood, but did not alter the clinical phenotype. The relatively mild phenotype of these mice mimics patients with milder PEX7 defects, and highlights the skeleton and lens as sensitive markers of plasmalogen deficiency. The role of plasmalogens in the normal function of these tissues at various ages can now be studied and additional therapeutic interventions tested in this model.


Assuntos
Osso e Ossos/metabolismo , Condrodisplasia Punctata Rizomélica/genética , Modelos Animais de Doenças , Cristalino/patologia , Peroxissomos/fisiologia , Plasmalogênios/metabolismo , Receptores Citoplasmáticos e Nucleares/deficiência , Animais , Células Cultivadas , Condrodisplasia Punctata Rizomélica/terapia , Suplementos Nutricionais , Éteres de Glicerila/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptor 2 de Sinal de Orientação para Peroxissomos , Fenótipo , Ácido Fitânico/metabolismo , Distribuição Tecidual
8.
Exp Clin Transplant ; 6(2): 118-26, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18816238

RESUMO

OBJECTIVES: The present study, registered at clinicaltrials.gov with the unique registration number NCT00560014, sought to evaluate the relations between fatty acid concentrations in red blood cells or plasma and amino acid concentrations in plasma on rejection, calcineurin inhibitor toxicity, and new-onset diabetes mellitus. MATERIALS AND METHODS: Lipid profiles on plasma or red blood cell samples were performed preoperatively and postoperatively in 54 patients. Plasma amino acid profiles were obtained in 49 of these patients. RESULTS: High concentrations of total omega-3 fatty acids, eicosapentaenoic and docosahexaenoic acids in red blood cells, and ornithine in plasma, all were associated with a significantly lower incidence of rejection, whereas high total omega-6 fatty acids were associated with a high rejection rate. Calcineurin inhibitor toxicity was associated with low levels of docosahexaenoic acid, ornithine, and the omega-3 index, and high total omega-6 and omega-3/omega-6 ratios. Inhibition of new-onset diabetes mellitus was seen only with high levels of ornithine. Peak concentrations of fatty acids in red blood cells were not obtained until after 30 days. High levels of arginine were not associated with reduced complications. CONCLUSIONS: The levels of selected nutrients in plasma and red blood cell membranes appear to have a profound effect on complications after renal transplant. These preliminary results need confirmation in prospective randomized clinical trials.


Assuntos
Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Transplante de Rim , Ornitina/sangue , Complicações Pós-Operatórias , Adulto , Arginina/administração & dosagem , Arginina/uso terapêutico , Inibidores de Calcineurina , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/prevenção & controle , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/uso terapêutico , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/uso terapêutico , Ácidos Graxos Monoinsaturados/administração & dosagem , Ácidos Graxos Monoinsaturados/uso terapêutico , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/efeitos adversos , Incidência , Masculino , Pessoa de Meia-Idade , Óleo de Brassica napus
9.
Arch Ophthalmol ; 122(9): 1306-14, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15364709

RESUMO

OBJECTIVE: To determine whether docosahexaenoic acid will slow the course of retinal degeneration in subgroups of patients with retinitis pigmentosa who are receiving vitamin A. DESIGN: A cohort of 208 patients with retinitis pigmentosa, aged 18 to 55 years, were randomly assigned to 1200 mg of docosahexaenoic acid plus 15 000 IU/d of vitamin A given as retinyl palmitate (DHA + A group) or control fatty acid plus 15 000 IU/d of vitamin A (control + A group) and followed up over 4 years. Seventy percent of the patients in each group were taking vitamin A, 15 000 IU/d, prior to entry. We compared rates of decline in ocular function in the DHA + A vs control + A groups among the subgroups defined by use or nonuse of vitamin A prior to entry. We also determined whether decline in ocular function was related to red blood cell phosphatidylethanolamine docosahexaenoic acid level, dietary omega-3 fatty acid intake, or duration of vitamin A use. Main outcome measures were Humphrey Field Analyzer visual field sensitivity, 30-Hz electroretinogram amplitude, and visual acuity. RESULTS: Among patients not taking vitamin A prior to entry, those in the DHA + A group had a slower decline in field sensitivity and electroretinogram amplitude than those in the control + A group over the first 2 years (P =.01 and P =.03, respectively); these differences were not observed in years 3 and 4 of follow-up or among patients taking vitamin A prior to entry. In the entire cohort, red blood cell phosphatidylethanolamine docosahexaenoic acid level was inversely related to rate of decline in total field sensitivity over 4 years (test for trend, P =.05). This was particularly evident over the first 2 years among those not on vitamin A prior to entry (test for trend, P =.003). In the entire control + A group, dietary omega-3 fatty acid intake was inversely related to loss of total field sensitivity over 4 years (intake, <0.20 vs > or =0.20 g/d; P =.02). The duration of vitamin A supplementation prior to entry was inversely related to rate of decline in electroretinogram amplitude (P =.008). CONCLUSIONS: For patients with retinitis pigmentosa beginning vitamin A therapy, addition of docosahexaenoic acid, 1200 mg/d, slowed the course of disease for 2 years. Among patients on vitamin A for at least 2 years, a diet rich in omega-3 fatty acids (> or =0.20 g/d) slowed the decline in visual field sensitivity.


Assuntos
Ácidos Docosa-Hexaenoicos/uso terapêutico , Retinose Pigmentar/tratamento farmacológico , Vitamina E/uso terapêutico , Administração Oral , Adolescente , Adulto , Ácidos Docosa-Hexaenoicos/metabolismo , Método Duplo-Cego , Quimioterapia Combinada , Eletrorretinografia , Membrana Eritrocítica/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatidiletanolaminas/metabolismo , Retina/fisiopatologia , Retinose Pigmentar/fisiopatologia , Transtornos da Visão/tratamento farmacológico , Transtornos da Visão/fisiopatologia , Campos Visuais/fisiologia
10.
Arch Ophthalmol ; 122(9): 1297-305, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15364708

RESUMO

OBJECTIVE: To determine whether a therapeutic dose of docosahexaenoic acid (DHA), an omega-3 fatty acid, will slow the course of retinal degeneration in adult patients with retinitis pigmentosa who are also receiving vitamin A. DESIGN: Randomized, controlled, double-masked trial of 221 patients, aged 18 to 55 years, evaluated over a 4-year interval. Patients were given either 1200 mg/d of docosahexaenoic acid or control capsules. All were given 15 000 IU/d of vitamin A (given as retinyl palmitate). Randomization considered genetic type and baseline dietary omega-3 fatty acid intake. MAIN OUTCOME MEASURES: The primary outcome measure was the total point score for the 30-2 program of the Humphrey field analyzer; secondary outcome measures were the total point score for the 30-2 and 30/60-1 programs combined, 30-Hz electroretinogram amplitude, and Early Treatment Diabetic Rentinopathy Study visual acuity. RESULTS: No significant differences in decline in ocular function were found between the docosahexaenoic acid plus vitamin A (DHA + A) group and control plus vitamin A (control + A) group over a 4-year interval among all 221 randomized patients or among the 208 patients who completed all 4 follow-up visits. The mean annual rate of loss of sensitivity for the Humphrey Field Analyzer 30-2 program was 37 dB for the DHA + A group and 38 dB for the control + A group (P =.88). For the Humphrey Field Analyzer 30-2 and 30/60-1 programs combined, the mean annual rates of loss of field sensitivity were 57 dB for the DHA + A group and 60 dB (P =.73) for control + A group. No toxic adverse effects were observed. No significant differences by treatment group assignment were observed within genetic types or within the category of baseline omega-3 fatty acid intake. CONCLUSION: In patients assigned to receive 15 000 IU/d of vitamin A, this randomized trial showed that 1200 mg/d of docosahexaenoic acid supplementation over a 4-year interval did not, on average, slow the course of disease in patients with retinitis pigmentosa.


Assuntos
Ácidos Docosa-Hexaenoicos/uso terapêutico , Retinose Pigmentar/tratamento farmacológico , Vitamina E/uso terapêutico , Administração Oral , Adolescente , Adulto , Método Duplo-Cego , Quimioterapia Combinada , Eletrorretinografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Retinose Pigmentar/fisiopatologia , Transtornos da Visão/tratamento farmacológico , Transtornos da Visão/fisiopatologia , Campos Visuais/fisiologia
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