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1.
Am J Respir Crit Care Med ; 202(3): 371-382, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32186892

RESUMEN

Rationale: Vitamin D deficiency is common in patients with asthma and chronic obstructive pulmonary disease (COPD). Low 25-hydroxyvitamin D (25[OH]D) levels may represent a cause or a consequence of these conditions.Objectives: To determine whether vitamin D metabolism is altered in asthma or COPD.Methods: We conducted a longitudinal study in 186 adults to determine whether the 25(OH)D response to six oral doses of 3 mg vitamin D3, administered over 1 year, differed between those with asthma or COPD versus control subjects. Serum concentrations of vitamin D3, 25(OH)D3, and 1α,25-dihydroxyvitamin D3 (1α,25[OH]2D3) were determined presupplementation and postsupplementation in 93 adults with asthma, COPD, or neither condition, and metabolite-to-parent compound molar ratios were compared between groups to estimate hydroxylase activity. Additionally, we analyzed 14 datasets to compare expression of 1α,25(OH)2D3-inducible gene expression signatures in clinical samples taken from adults with asthma or COPD versus control subjects.Measurements and Main Results: The mean postsupplementation 25(OH)D increase in participants with asthma (20.9 nmol/L) and COPD (21.5 nmol/L) was lower than in control subjects (39.8 nmol/L; P = 0.001). Compared with control subjects, patients with asthma and COPD had lower molar ratios of 25(OH)D3-to-vitamin D3 and higher molar ratios of 1α,25(OH)2D3-to-25(OH)D3 both presupplementation and postsupplementation (P ≤ 0.005). Intergroup differences in 1α,25(OH)2D3-inducible gene expression signatures were modest and variable if statistically significant.Conclusions: Attenuation of the 25(OH)D response to vitamin D supplementation in asthma and COPD associated with reduced molar ratios of 25(OH)D3-to-vitamin D3 and increased molar ratios of 1α,25(OH)2D3-to-25(OH)D3 in serum, suggesting that vitamin D metabolism is dysregulated in these conditions.


Asunto(s)
Asma/metabolismo , Calcifediol/metabolismo , Calcitriol/metabolismo , Colecalciferol/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Vitaminas/metabolismo , 25-Hidroxivitamina D3 1-alfa-Hidroxilasa/genética , Estudios de Casos y Controles , Colecalciferol/farmacocinética , Colestanotriol 26-Monooxigenasa/genética , Citocromo P-450 CYP3A/genética , Familia 2 del Citocromo P450/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Polimorfismo de Nucleótido Simple , Ensayos Clínicos Controlados Aleatorios como Asunto , Proteína de Unión a Vitamina D/genética , Vitamina D3 24-Hidroxilasa/genética , Vitaminas/farmacocinética
2.
Neurotoxicology ; 51: 38-50, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26386148

RESUMEN

Exposure to nerve agents results in severe seizures or status epilepticus caused by the inhibition of acetylcholinesterase, a critical enzyme that breaks down acetylcholine to terminate neurotransmission. Prolonged seizures cause brain damage and can lead to long-term consequences. Current countermeasures are only modestly effective against the brain damage supporting interest in the evaluation of new and efficacious therapies. The nutraceutical alpha-linolenic acid (LIN) is an essential omega-3 polyunsaturated fatty acid that has a wide safety margin. Previous work showed that a single intravenous injection of alpha-linolenic acid (500 nmol/kg) administered before or after soman significantly protected against soman-induced brain damage when analyzed 24h after exposure. Here, we show that administration of three intravenous injections of alpha-linolenic acid over a 7 day period after soman significantly improved motor performance on the rotarod, enhanced memory retention, exerted an anti-depressant-like activity and increased animal survival. This dosing schedule significantly reduced soman-induced neuronal degeneration in four major vulnerable brain regions up to 21 days. Taken together, alpha-linolenic acid reduces the profound behavioral deficits induced by soman possibly by decreasing neuronal cell death, and increases animal survival.


Asunto(s)
Antidepresivos/administración & dosificación , Cognición/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Soman/toxicidad , Ácido alfa-Linolénico/administración & dosificación , Animales , Reacción de Prevención/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/patología , Suplementos Dietéticos , Masculino , Actividad Motora/efectos de los fármacos , Neuronas/efectos de los fármacos , Ratas Sprague-Dawley , Prueba de Desempeño de Rotación con Aceleración Constante
3.
Proc Natl Acad Sci U S A ; 107(15): 6759-64, 2010 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-20351276

RESUMEN

The Farming/Language Dispersal Hypothesis posits that prehistoric population expansions, precipitated by the innovation or early adoption of agriculture, played an important role in the uneven distribution of language families recorded across the world. In this case, the most widely spread language families today came to be distributed at the expense of those that have more restricted distributions. In the Americas, Uto-Aztecan is one such language family that may have been spread across Mesoamerica and the American Southwest by ancient farmers. We evaluated this hypothesis with a large-scale study of mitochondrial DNA (mtDNA) and Y-chromosomal DNA variation in indigenous populations from these regions. Partial correlation coefficients, determined with Mantel tests, show that Y-chromosome variation in indigenous populations from the American Southwest and Mesoamerica correlates significantly with linguistic distances (r = 0.33-0.384; P < 0.02), whereas mtDNA diversity correlates significantly with only geographic distance (r = 0.619; P = 0.002). The lack of correlation between mtDNA and Y-chromosome diversity is consistent with differing population histories of males and females in these regions. Although unlikely, if groups of Uto-Aztecan speakers were responsible for the northward spread of agriculture and their languages from Mesoamerica to the Southwest, this migration was possibly biased to males. However, a recent in situ population expansion within the American Southwest (2,105 years before present; 99.5% confidence interval = 1,273-3,773 YBP), one that probably followed the introduction and intensification of maize agriculture in the region, may have blurred ancient mtDNA patterns, which might otherwise have revealed a closer genetic relationship between females in the Southwest and Mesoamerica.


Asunto(s)
Cromosomas Humanos Y/ultraestructura , ADN Mitocondrial/ultraestructura , Variación Genética , Indígenas Norteamericanos/genética , Lenguaje , Agricultura/métodos , Evolución Biológica , América Central , Emigración e Inmigración , Etnicidad/genética , Femenino , Genética de Población , Historia Antigua , Humanos , Indígenas Norteamericanos/historia , Masculino , Datos de Secuencia Molecular , Factores Sexuales , Sudoeste de Estados Unidos , Zea mays/metabolismo
4.
Am J Phys Anthropol ; 132(4): 605-21, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17243155

RESUMEN

Mitochondrial and Y-chromosome DNA were analyzed from 10,300-year-old human remains excavated from On Your Knees Cave on Prince of Wales Island, Alaska (Site 49-PET-408). This individual's mitochondrial DNA (mtDNA) represents the founder haplotype of an additional subhaplogroup of haplogroup D that was brought to the Americas, demonstrating that widely held assumptions about the genetic composition of the earliest Americans are incorrect. The amount of diversity that has accumulated in the subhaplogroup over the past 10,300 years suggests that previous calibrations of the mtDNA clock may have underestimated the rate of molecular evolution. If substantiated, the dates of events based on these previous estimates are too old, which may explain the discordance between inferences based on genetic and archaeological evidence regarding the timing of the settlement of the Americas. In addition, this individual's Y-chromosome belongs to haplogroup Q-M3*, placing a minimum date of 10,300 years ago for the emergence of this haplogroup.


Asunto(s)
Huesos/química , Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Evolución Molecular , Fósiles , Indígenas Norteamericanos/genética , Filogenia , Dinámica Poblacional , Alaska , Secuencia de Bases , Cartilla de ADN , Haplotipos/genética , Historia Antigua , Humanos , Funciones de Verosimilitud , Masculino , Modelos Genéticos , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
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