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1.
Chem Biol Drug Des ; 95(1): 66-78, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31469231

RESUMEN

High-throughput assays are a common strategy for the identification of compounds able to modulate a certain cellular activity. Here, we show an automatized analysis platform for the quantification of nuclear foci as inhibitory effect of compounds on a target protein labeled by fluorescent antibodies. Our experience led us to a fast analysis platform that combines cell-based assays, high-content screening, and confocal microscopy, with an automatic and user-friendly statistical analysis of plate-based assays including positive and negative controls, able to identify inhibitory effect of compounds tested together with the Z-prime and Window of individual plate-based assays to assess the reliability of the results. The platform integrates a web-based tool implemented in Pipeline Pilot and R, and allows computing the inhibition values of different parameters obtained from the high-content screening and confocal microscopy analysis. This facilitates the exploration of the results using the different parameters, providing information at different levels as the number of foci observed, the sum of intensity of foci, area of foci, etc, the detection and filtering of outliers over the assay plate, and finally providing a set of statistics of the parameters studied together with a set of plots that we believe significantly helps to the interpretation of the assay results.


Asunto(s)
Técnica del Anticuerpo Fluorescente/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/metabolismo , Proteína 1 de Unión a Repeticiones Teloméricas/metabolismo , Anticuerpos/inmunología , Línea Celular Tumoral , Evaluación Preclínica de Medicamentos/métodos , Colorantes Fluorescentes/química , Humanos , Microscopía Confocal , Imagen Óptica , Reproducibilidad de los Resultados , Telómero/metabolismo , Telómero/ultraestructura
2.
Nutr Hosp ; 36(6): 1403-1417, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31657606

RESUMEN

INTRODUCTION: Telomere length (TL) is a predictive biomarker of premature aging. Telomere shortening has been linked to age-related diseases and noncommunicable diseases (NCD), and may reflect the effects of behavioral, psychosocial and environmental factors on health status. Telomere attrition can be affected by lifestyle factors such as diet and physical activity. The search of studies included in this review was conducted on PubMed Central database. A majority of studies are cross-sectional, as there is a clear lack of prospective studies to evaluate the individual effect of dietary components, dietary patterns, and physical activity on TL in the long term. The current literature suggests that high adherence to Mediterranean diet (MD), with consumption of antioxidants, fiber and vegetables, as well as seeds and walnuts, is associated with longer TL. The dietary components of a healthy diet, such as carotenoids, vitamins A, C, D, E, polyphenols, fiber, and omega-3 fatty acids could help maintain TL. In contrast, a high consumption of sugary beverages, processed meat, and proinflammatory diets is associated with telomere shortening. In a majority of studies TL is positively associated with moderate physical activity. The predominant mechanisms through which a healthy diet and moderate physical exercise could mitigate telomere attrition include decreasing oxidative stress and inflammation. We shall not discuss the associations of possible risk or protective factors in terms of causality since the majority of studies are cross-sectional and randomized controlled trials are limited; accordingly, some results are inconclusive. For future research, we suggest evaluating the individual effects of dietary components, dietary patterns and physical activity, considering repeated measurements and exercise intensity, on TL. It is also advisable to include biomarkers of oxidative stress and inflammation proteins, and to measure telomerase activity.


INTRODUCCIÓN: La longitud de los telómeros (TL) es un biomarcador predictivo del envejecimiento prematuro. El acortamiento de los telómeros se ha relacionado con las enfermedades asociadas a la edad y las enfermedades no transmisibles (ENT), y puede reflejar los efectos de los factores conductuales, psicosociales y ambientales en el estado de salud. El desgaste de los telómeros puede verse afectado por factores del estilo de vida, como la dieta y la actividad física. La búsqueda de los estudios incluidos en esta revisión se realizó en la base de datos PubMed Central. La mayoría de los estudios son transversales, por lo que está clara la falta de estudios prospectivos que evalúen el efecto individual de los componentes dietéticos, los patrones dietéticos y la actividad física sobre el TL a largo plazo. Los componentes dietéticos de una dieta saludable, como los carotenoides, las vitaminas A, C, D, E, los polifenoles, la fibra y los ácidos grasos omega-3, podrían ayudar a mantener la TL. En contraste, el alto consumo de bebidas azucaradas, carne procesada y dietas proinflamatorias se asocia al acortamiento de los telómeros. En la mayoría de los estudios, el TL se asocia positivamente con la actividad física moderada. Los mecanismos predominantes que podrían mitigar el desgaste de los telómeros son la disminución del estrés oxidativo y la inflamación. No se discute la asociación de posibles factores de riesgo o de protección en términos de causalidad, ya que la mayoría de los estudios son transversales y los ensayos controlados aleatorios son limitados; por consiguiente, algunos resultados no son concluyentes. Para investigaciones futuras se sugiere evaluar los efectos individuales de los componentes dietéticos, los patrones de actividad física y dietética. También es aconsejable incluir biomarcadores de estrés oxidativo y proteínas inflamatorias, y medir la actividad de la telomerasa.


Asunto(s)
Dieta , Ejercicio Físico , Telómero/ultraestructura , Investigación Biomédica/tendencias , Ácidos Grasos Esenciales , Predicción , Humanos , Inflamación , Micronutrientes , Estrés Oxidativo
3.
Nutr Hosp ; 35(3): 570-575, 2018 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-29974764

RESUMEN

INTRODUCTION: inflammation and oxidative stress are factors that may play a substantial role in telomere attrition. In line of this, obesity is associated with telomere shortening. Green tea had anti-inflammatory and antioxidant effects and may alter telomere length (TL). OBJECTIVES: we evaluated the effect of decaffeinated green tea supplementation in obese women on TL. METHODS: we conducted a cross-sectional interventional study with ten obese (body mass index [BMI] > 40 kg/m²) and eight normal weight (BMI > 18.5 and < 24.9 kg/m²) women (age between 27 and 48 years). The supplementation was carried out with capsules (each contained 450.7 mg of epigallocatechin-3-gallate) during eight weeks. Anthropometric and dietary intake assessment, and blood collection (for biochemical and TL analysis by quantitative PCR) were performed before and after supplementation. Normal weight patients were evaluated at a single moment. RESULTS: we observed a significant increase on TL after supplementation (1.57 ± 1.1 to 3.2 ± 2.1 T/Sratio; p < 0.05). Moreover, we found shorter TL in obese patients (day 0) when compared to normal weight individuals (3.2 ± 1.9 T/Sratio; p < 0.05) and an inverse association between TL and BMI, even after age adjustment (beta = -0.527; r² = 0.286; IC = -0.129, -0.009). CONCLUSION: obesity is related to shorter telomeres. Green tea supplementation during eight weeks promotes telomere elongation in obese women.


Asunto(s)
Catequina/análogos & derivados , Suplementos Dietéticos , Leucocitos/ultraestructura , Obesidad/dietoterapia , , Telómero/ultraestructura , Adulto , Índice de Masa Corporal , Catequina/farmacología , Estudios Transversales , Femenino , Humanos , Leucocitos/efectos de los fármacos , Persona de Mediana Edad , Obesidad/sangre , Telómero/efectos de los fármacos , Acortamiento del Telómero
4.
Theor Appl Genet ; 130(9): 1785-1800, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28550436

RESUMEN

KEY MESSAGE: Exposure of wheat to high temperatures during male meiosis prevents normal meiotic progression and reduces grain number. We define a temperature-sensitive period and link heat tolerance to chromosome 5D. This study assesses the effects of heat on meiotic progression and grain number in hexaploid wheat (Triticum aestivum L. var. Chinese Spring), defines a heat-sensitive stage and evaluates the role of chromosome 5D in heat tolerance. Plants were exposed to high temperatures (30 or 35 °C) in a controlled environment room for 20-h periods during meiosis and the premeiotic interphase just prior to meiosis. Examination of pollen mother cells (PMCs) from immature anthers immediately before and after heat treatment enabled precise identification of the developmental phases being exposed to heat. A temperature-sensitive period was defined, lasting from premeiotic interphase to late leptotene, during which heat can prevent PMCs from progressing through meiosis. PMCs exposed to 35 °C were less likely to progress than those exposed to 30 °C. Grain number per spike was reduced at 30 °C, and reduced even further at 35 °C. Chinese Spring nullisomic 5D-tetrasomic 5B (N5DT5B) plants, which lack chromosome 5D, were more susceptible to heat during premeiosis-leptotene than Chinese Spring plants with the normal (euploid) chromosome complement. The proportion of plants with PMCs progressing through meiosis after heat treatment was lower for N5DT5B plants than for euploids, but the difference was not significant. However, following exposure to 30 °C, in euploid plants grain number was reduced (though not significantly), whereas in N5DT5B plants the reduction was highly significant. After exposure to 35 °C, the reduction in grain number was highly significant for both genotypes. Implications of these findings for the breeding of thermotolerant wheat are discussed.


Asunto(s)
Calor , Meiosis , Polen/genética , Triticum/genética , Grano Comestible/citología , Grano Comestible/genética , Poliploidía , Estrés Fisiológico , Telómero/ultraestructura , Triticum/citología
5.
Eur J Nutr ; 56(5): 1887-1898, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27379829

RESUMEN

BACKGROUND: Vitamin B deficiency is common in elderly people and has been associated with an increased risk of developing age-related diseases. B-vitamins are essential for the synthesis and stability of DNA. Telomers are the end caps of chromosomes that shorten progressively with age, and short telomers are associated with DNA instability. OBJECTIVE: In the present randomized intervention study, we investigated whether the one-carbon metabolism is related to telomere length, a surrogate marker for cellular aging. DESIGN: Sixty-five subjects (>54 years) were randomly assigned to receive either a daily combination of vitamin D3 (1200 IU), folic acid (0.5 mg), vitamin B12 (0.5 mg), vitamin B6 (50 mg) and calcium carbonate (456 mg) (group A) or vitamin D3 and calcium carbonate alone (group B). Blood testing was performed at baseline and after 1 year of supplementation. The concentrations of several metabolites of the one-carbon pathway, as well as relative telomere length (RTL) and 5,10-methylenetetrahydrofolate reductase C677T genotype, were analyzed. RESULTS: At baseline, age- and gender-adjusted RTL correlated with total folate and 5-methyltetrahydrofolate (5-methylTHF). Subjects with RTL above the median had higher concentrations of total folate and 5-methylTHF compared to subjects below the median. At study end, gender- and age-adjusted RTL correlated in group A with methylmalonic acid (MMA; r = -0.460, p = 0.0012) and choline (r = 0.434, p = 0.0021) and in group B with 5,10-methenyltetrahydrofolate (r = 0.455, p = 0.026) and dimethylglycine (DMG; r = -0.386, p = 0.047). Subjects in the group A with RTL above the median had lower MMA and higher choline compared to subjects below the median. CONCLUSIONS: The present pilot study suggests a functional relationship between one-carbon metabolism and telomere length. This conclusion is supported by several correlations that were modified by B-vitamin supplementation. In agreement with our hypothesis, the availability of nucleotides and methylation groups seems to impact telomere length. Due to the small sample size and the limitations of the study, further studies should confirm the present results in a larger cohort.


Asunto(s)
Carbono/metabolismo , Suplementos Dietéticos , Homeostasis del Telómero , Telómero/ultraestructura , Complejo Vitamínico B/administración & dosificación , Vitamina D/administración & dosificación , Anciano , Biomarcadores/sangre , Índice de Masa Corporal , Carbonato de Calcio/administración & dosificación , Colina/sangre , Estudios Transversales , Método Doble Ciego , Femenino , Ácido Fólico/administración & dosificación , Ácido Fólico/sangre , Humanos , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2)/sangre , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Ácido Metilmalónico/sangre , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Sarcosina/análogos & derivados , Sarcosina/sangre , Tetrahidrofolatos/sangre , Vitamina B 12/administración & dosificación , Vitamina B 12/sangre , Vitamina B 6/administración & dosificación , Vitamina B 6/sangre , Complejo Vitamínico B/sangre , Vitamina D/sangre
6.
J Nutr ; 146(7): 1373-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27281805

RESUMEN

BACKGROUND: Coffee is an important source of antioxidants, and consumption of this beverage is associated with many health conditions and a lower mortality risk. However, no study, to our knowledge, has examined whether varying coffee or caffeine consumption levels are associated with telomere length, a biomarker of aging whose shortening can be accelerated by oxidative stress. OBJECTIVE: We performed a large comprehensive study on how coffee consumption is associated with telomere length. METHODS: We used data from the Nurses' Health Study (NHS), a prospective cohort study of female nurses that began in 1976. We examined the cross-sectional association between coffee consumption and telomere length in 4780 women from the NHS. Coffee consumption information was obtained from validated food-frequency questionnaires, and relative telomere length was measured in peripheral blood leukocytes by the quantitative real-time polymerase chain reaction. Unconditional logistic regression was used to obtain ORs when the telomere length outcome was dichotomized at the median. Linear regression was used for tests of trend with coffee consumption and telomere length as continuous variables. RESULTS: Higher total coffee consumption was significantly associated with longer telomeres after potential confounding adjustment. Compared with non-coffee drinkers, multivariable ORs for those drinking 2 to <3 and ≥3 cups of coffee/d were, respectively, 1.29 (95% CI: 0.99, 1.68) and 1.36 (95% CI: 1.04, 1.78) (P-trend = 0.02). We found a significant linear association between caffeine consumption from all dietary sources and telomere length (P-trend = 0.02) after adjusting for potential confounders, but not after additionally adjusting for total coffee consumption (P-trend = 0.37). CONCLUSIONS: We found that higher coffee consumption is associated with longer telomeres among female nurses. Future studies are needed to better understand the influence of coffee consumption on telomeres, which may uncover new knowledge of how coffee consumption affects health and longevity.


Asunto(s)
Café/química , Leucocitos/ultraestructura , Adulto , Anciano , Cafeína/administración & dosificación , Cafeína/química , Estudios Transversales , Dieta , Registros de Dieta , Encuestas sobre Dietas , Femenino , Humanos , Persona de Mediana Edad , Telómero/ultraestructura
7.
Bioelectrochemistry ; 107: 25-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26457533

RESUMEN

Human telomeric DNA typically consists of many tandem repeats of the guanine-rich sequences d (TTAGGG) termed an intermolecular Gquadruplex structure. This structure plays an important role in the protection, stabilization and replication of chromosome ends and so is an active target for therapeutic purposes. Recently ligands that are able to stabilize Gquadruplex structure, have received great attention because quadruplex-binding ligands have potential applications in cancer therapy. The screen-printed graphite electrode (SPE) was modified with synthesized SBA-N-propylpipyrazine-N-(2-mercaptopropane-1-one) (SBA-NPPNSH) mesoporous structure to investigate the Gquadruplex DNA (G4DNA) formation and stabilization. Differential pulse voltammetry was used to examine the stability and formation of G4DNA in various K(+) concentrations, under different pH conditions and also in the presence of positive and negative G4DNA-binding ligands. The stability effect of TMPyP4 as a positive G4DNA-binding ligand was examined in the presence of complementary G4DNA strands. This studying revealed that after adding K(+) or positive G4DNA-binding ligand a new peak observed in higher potential due to oxidation of guanine residuals in the Gquadruplex structure.


Asunto(s)
Antineoplásicos/análisis , Técnicas Biosensibles/métodos , G-Cuádruplex , Telómero/ultraestructura , Antineoplásicos/química , Técnicas Biosensibles/instrumentación , Electroquímica , Electrodos , Grafito , Guanina/química , Humanos , Ligandos , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Piperazinas/química , Potasio/química , Dióxido de Silicio/química , Propiedades de Superficie
8.
Toxicol Ind Health ; 32(12): 1961-1970, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26381690

RESUMEN

The negative health effects caused by lead (Pb) exposure are widely recognized; however, the molecular mechanisms remain unknown. The aim of this study was to assess the effect of occupational Pb exposure on telomere length and to investigate the potential mechanisms leading to telomere shortening. A cohort of 334 male Pb smelters (exposed group) and 60 age-adjusted males unexposed to Pb (control group) were examined. Assessments of relative telomere length (rTL) and telomerase reverse transcriptase (TERT) gene expression were performed using quantitative real-time polymerase chain reactions. Assessments of whole blood Pb (B-Pb) and whole blood cadmium (B-Cd) concentrations and serum selenium concentration (S-Se) were performed using graphite furnace atomic absorption spectrometry. We analyzed total oxidation status (TOS), lipid hydroperoxides (LHPs), malonylodialdehyde levels in serum (MDA) and in erythrocyte hemolysates (MDA-hgb), and 8-hydroxy-deoxy-guanosine (8-OHdG). The Pb-exposed group had higher B-Pb values and shorter rTL than the control group. The arithmetic mean values calculated for B-Pb were 33 µg/dL versus 2.2 µg/dL (p < 0.0001), and the rTL values were 0.928 and 1.126 relative units (p = 0.001), respectively, for the Pb-exposed and control groups. The rTL was found to gradually shorten in response to the increasing levels of Pb exposure. The Pb-exposed group also demonstrated a higher level of oxidative stress than the control group, which was indicated by increased TOS and MDA-hgb values. rTL was negatively associated with parameters that indicated increased oxidative stress, including TOS (Spearman's rank coefficient (rS) = -0.16; p < 0.01) and MDA-hgb (rS = -0.17; p < 0.001). No correlations were found between rTL and B-Cd and S-Se or smoking and MDA and LHP levels. Univariate analysis indicated that B-Pb was associated with decreased rTL (ß =-0.0041; p = 0.0063) and that the association between B-Pb and rTL remained significant, even when adjusting for age (ß = -0.0041; p = 0.0065) and in multivariable-adjusted model (ß = -0.0042; p = 0.0063). In conclusion, occupational Pb exposure resulted in decreased rTL and may represent a mechanism that contributes to Pb-related diseases.


Asunto(s)
Plomo/toxicidad , Exposición Profesional/efectos adversos , Estrés Oxidativo/genética , Telomerasa/metabolismo , Telómero/ultraestructura , 8-Hidroxi-2'-Desoxicoguanosina , Cadmio/sangre , Cadmio/toxicidad , Estudios de Casos y Controles , Estudios de Cohortes , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangre , Humanos , Plomo/sangre , Peróxidos Lipídicos/sangre , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Selenio/sangre , Espectrofotometría Atómica , Telomerasa/genética
9.
Eur J Nutr ; 55(5): 1863-73, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26293976

RESUMEN

PURPOSE: Deficiencies of folate, vitamins B12 and D are common age-related conditions. Vitamin B12 and folate are necessary for DNA methylation. Telomeres appear to be regulated by DNA methylation. Here, we study the effect of B vitamins supplementation on telomere length and global DNA methylation in a prospective study. METHODS: In total, 60 elderly subjects were supplemented for 1 year with either vitamin B12, B6, folate, vitamin D and calcium (group A n = 31) or only vitamin D and calcium (group B n = 29). LINE-1 methylation, relative telomere length (T/S), vitamin B12, folate, homocysteine (tHcy) , 5-methyltetrahydrofolate (5-methylTHF), S-adenosylhomocysteine (SAH), S-adenosylmethionine (SAM), cystathionine and vitamin D were quantified before and after supplementation. RESULTS: At baseline, tHcy was high, vitamin D was low, and T/S did not differ between groups A and B. Vitamin supplementation increased LINE-1 methylation in group A at site 317 but reduced LINE-1 methylation in group B at site 327. There was no correlation between T/S and LINE-1 methylation at baseline. Multiple backward regression analysis revealed baseline tHcy and 5-methylTHF are significant predictors of T/S. After supplementation in group B but not in group A, LINE-1 methylation correlated inversely with T/S, and LINE-1 methylation variation was an independent predictor of T/S variation. B vitamins decreased tHcy significantly in group A. Multiple backward regression analysis showed 5-methylTHF in group A and tHcy in group B were significant predictors for LINE-1 methylation. At baseline, the lower LINE-1 methylation observed in subjects with 5-methylTHF >10 nmol/l was in agreement with a reduced methyl group transfer due to a lower SAM formation. In group B, an increase in telomere length was correlated with lower LINE-1 methylation. Subjects with hyperhomocysteinemia >12 µmol/L had compared to those with normal tHcy a reduced LINE-1 methylation accompanied by a higher SAM and SAH (that inhibits demethylation of SAM) as well as lower 5-methylTHF. Additionally, subjects with tHcy > 12 µmol/L had longer telomeres when compared with subjects having tHcy < 12 µmol/L. CONCLUSIONS: The results suggest a possible effect of B vitamins for telomere biology in blood cells. Suboptimal B vitamins status and hyperhomocysteinemia are associated with altered DNA methylation and telomere length. These data have to be confirmed in future studies.


Asunto(s)
Células Sanguíneas/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Suplementos Dietéticos , Elementos de Nucleótido Esparcido Largo/genética , Telómero/ultraestructura , Complejo Vitamínico B/administración & dosificación , Anciano , Calcio/administración & dosificación , Calcio/sangre , Estudios Transversales , Femenino , Ácido Fólico/administración & dosificación , Ácido Fólico/sangre , Homocisteína/sangre , Humanos , Hiperhomocisteinemia/tratamiento farmacológico , Modelos Lineales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , S-Adenosilhomocisteína/sangre , S-Adenosilmetionina/sangre , Tetrahidrofolatos/sangre , Vitamina B 12/administración & dosificación , Vitamina B 12/sangre , Vitamina B 6/administración & dosificación , Vitamina B 6/sangre , Complejo Vitamínico B/sangre , Vitamina D/administración & dosificación , Vitamina D/sangre
10.
Brain Behav Immun ; 32: 159-63, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23602876

RESUMEN

Relatively short telomere length may serve as a marker of accelerated aging, and shorter telomeres have been linked to chronic stress. Specific lifestyle behaviors that can mitigate the effects of stress might be associated with longer telomere lengths. Previous research suggests a link between behaviors that focus on the well-being of others, such as volunteering and caregiving, and overall health and longevity. We examined relative telomere length in a group of individuals experienced in Loving-Kindness Meditation (LKM), a practice derived from the Buddhist tradition which utilizes a focus on unselfish kindness and warmth towards all people, and control participants who had done no meditation. Blood was collected by venipuncture, and Genomic DNA was extracted from peripheral blood leukocytes. Quantitative real time PCR was used to measure relative telomere length (RTL) (Cawthon, 2002) in fifteen LKM practitioners and 22 control participants. There were no significant differences in age, gender, race, education, or exposure to trauma, but the control group had a higher mean body mass index (BMI) and lower rates of past depression. The LKM practitioners had longer RTL than controls at the trend level (p=.083); among women, the LKM practitioners had significantly longer RTL than controls, (p=.007), which remained significant even after controlling for BMI and past depression. Although limited by small sample size, these results offer the intriguing possibility that LKM practice, especially in women, might alter RTL, a biomarker associated with longevity.


Asunto(s)
Amor , Meditación/psicología , Telómero/fisiología , Telómero/ultraestructura , Adulto , Índice de Masa Corporal , ADN/genética , ADN/ultraestructura , Interpretación Estadística de Datos , Femenino , Humanos , Leucocitos/ultraestructura , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
11.
J Eur Acad Dermatol Venereol ; 27(10): 1222-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22946492

RESUMEN

BACKGROUND: Parthenium dermatitis is a common chronic inflammatory disease with activated T lymphocytes that recognize the antigens, which leads to proliferation and differentiation. Telomeres and telomerase play an important role in the regulation of life span of the cell. Telomere length maintained by telomerase, are specialized repeats present at the end of chromosomes which protect it from degradation, end-to-end fusion and are important for integrity of chromosomes. OBJECTIVES: The aim of this study was to measure telomerase activity and telomere length in Peripheral blood mononuclear cell (PBMC), CD4(+) and CD8(+) T lymphocytes from parthenium dermatitis patients. METHODS: The study includes 50 patients of parthenium dermatitis confirmed by patch testing and 50 healthy controls. Telomerase activity was measured using the telomere repeat amplification protocol using PCR-ELISA kit. Telomere length was measured by using Telo TAGGG Telomere Length Assay Kit. RESULTS: Significantly elevated levels of telomerase activity was observed in PBMC, CD4(+) and CD8(+) T cells of parthenium dermatitis patients as compared with healthy controls. However, significantly reduced telomere length in PBMC, CD4(+) and CD8(+) T cells have been found in patients than healthy subjects, but there was no difference between CD4(+) and CD8(+) T cells in patients. CONCLUSION: This study might have provided insight into the role of telomerase in parthenium dermatitis that is characterized by the recruitment of T lymphocytes, which play an important role in this inflammatory disease. The augmented telomerase activity and reduced terminal restriction fragment length might be explored as a potential diagnostic/prognostic marker for parthenium dermatitis in future.


Asunto(s)
Dermatitis por Contacto/metabolismo , Dermatitis por Contacto/patología , Extractos Vegetales/efectos adversos , Telomerasa/metabolismo , Acortamiento del Telómero , Adulto , Anciano , Biomarcadores/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Linfocitos T CD4-Positivos/ultraestructura , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Linfocitos T CD8-positivos/ultraestructura , Estudios de Casos y Controles , Femenino , Humanos , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/patología , Leucocitos Mononucleares/ultraestructura , Masculino , Persona de Mediana Edad , Partenogénesis , Pronóstico , Telómero/ultraestructura
12.
Dig Liver Dis ; 45(6): 499-504, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23238034

RESUMEN

BACKGROUND: Coffee is associated with a reduced risk of hepatocellular carcinoma in patients with chronic C hepatitis. This prospective trial was aimed at assessing the mechanisms underlying coffee-related protective effects. METHODS: Forty patients with chronic hepatitis C were randomized into two groups: the first consumed 4 cups of coffee/day for 30 days, while the second remained coffee "abstinent". At day 30, the groups were switched over for a second month. RESULTS: At baseline, aspartate aminotransferase and alanine aminotransferase were lower in patients drinking 3-5 (Group B) than 0-2 cups/day (Group A) (56 ± 6 vs 74 ± 11/60 ± 3 vs 73 ± 7 U/L p=0.05/p=0.04, respectively). HCV-RNA levels were significantly higher in Group B [(6.2 ± 1.5) × 10(5)vs (3.9 ± 1.0) × 10(5)UI/mL, p=0.05]. During coffee intake, 8-hydroxydeoxyguanosine and collagen levels were significantly lower than during abstinence (15 ± 3 vs 44 ± 16 8-hydroxydeoxyguanosine/10(5)deoxyguanosine, p=0.05 and 56 ± 9 vs 86 ± 21 ng/mL, p=0.04). Telomere length was significantly higher in patients during coffee intake (0.68 ± 0.06 vs 0.48 ± 0.04 Arbitrary Units, p=0.006). Telomere length and 8-hydroxydeoxyguanosine were inversely correlated. CONCLUSION: In chronic hepatitis C coffee consumption induces a reduction in oxidative damage, correlated with increased telomere length and apoptosis, with lower collagen synthesis, factors that probably mediate the protection exerted by coffee with respect to disease progression.


Asunto(s)
Café , Hepatitis C Crónica/prevención & control , 8-Hidroxi-2'-Desoxicoguanosina , Anciano , Alanina Transaminasa/sangre , Alanina Transaminasa/efectos de los fármacos , Aspartato Aminotransferasas/sangre , Aspartato Aminotransferasas/efectos de los fármacos , Cafeína/administración & dosificación , Colágeno/sangre , Colágeno/efectos de los fármacos , Estudios Cruzados , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangre , Femenino , Hepacivirus , Hepatitis C Crónica/enzimología , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , ARN Viral/sangre , ARN Viral/efectos de los fármacos , Telómero/efectos de los fármacos , Telómero/ultraestructura
13.
Mol Biol Cell ; 22(1): 12-9, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21119003

RESUMEN

During meiosis, the paired homologous chromosomes are tightly held together by the synaptonemal complex (SC). This complex consists of two parallel axial/lateral elements (AEs/LEs) and one central element. Here, we observed that PAIR3 localized to the chromosome core during prophase I and associated with both unsynapsed AEs and synapsed LEs. Analyses of the severe pair3 mutant demonstrated that PAIR3 was essential for bouquet formation, homologous pairing and normal recombination, and SC assembly. In addition, we showed that although PAIR3 was not required for the initial recruitment of PAIR2, it was required for the proper association of PAIR2 with chromosomes. Dual immunostaining revealed that PAIR3 highly colocalized with REC8. Moreover, studies using a rec8 mutant indicated that PAIR3 localized to chromosomes in a REC8-dependent manner.


Asunto(s)
Cromosomas de las Plantas/metabolismo , Meiosis , Proteínas Nucleares/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Recombinación Genética , Complejo Sinaptonémico/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Emparejamiento Cromosómico , Cromosomas de las Plantas/genética , Cromosomas de las Plantas/ultraestructura , Citocinesis , Hibridación Fluorescente in Situ , Profase Meiótica I/genética , Mutación , No Disyunción Genética , Proteínas Nucleares/genética , Oryza/fisiología , Proteínas de Plantas/genética , Polen , Complejo Sinaptonémico/ultraestructura , Telómero/ultraestructura
14.
Forensic Sci Int ; 203(1-3): 34-43, 2010 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-20702051

RESUMEN

Over the course of our lifetime a stochastic process leads to gradual alterations of biomolecules on the molecular level, a process that is called ageing. Important changes are observed on the DNA-level as well as on the protein level and are the cause and/or consequence of our 'molecular clock', influenced by genetic as well as environmental parameters. These alterations on the molecular level may aid in forensic medicine to estimate the age of a living person, a dead body or even skeletal remains for identification purposes. Four such important alterations have become the focus of molecular age estimation in the forensic community over the last two decades. The age-dependent accumulation of the 4977bp deletion of mitochondrial DNA and the attrition of telomeres along with ageing are two important processes at the DNA-level. Among a variety of protein alterations, the racemisation of aspartic acid and advanced glycation endproducs have already been tested for forensic applications. At the moment the racemisation of aspartic acid represents the pinnacle of molecular age estimation for three reasons: an excellent standardization of sampling and methods, an evaluation of different variables in many published studies and highest accuracy of results. The three other mentioned alterations often lack standardized procedures, published data are sparse and often have the character of pilot studies. Nevertheless it is important to evaluate molecular methods for their suitability in forensic age estimation, because supplementary methods will help to extend and refine accuracy and reliability of such estimates.


Asunto(s)
Envejecimiento/genética , Envejecimiento/fisiología , Ácido Aspártico/química , ADN Mitocondrial/genética , Productos Finales de Glicación Avanzada/metabolismo , Telómero/ultraestructura , Determinación de la Edad por los Dientes , Huesos/química , Esmalte Dental/química , Dentina/química , Medicina Legal , Humanos , Inmunohistoquímica , Eliminación de Secuencia , Telómero/genética
15.
JAMA ; 303(3): 250-7, 2010 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-20085953

RESUMEN

CONTEXT: Increased dietary intake of marine omega-3 fatty acids is associated with prolonged survival in patients with coronary heart disease. However, the mechanisms underlying this protective effect are poorly understood. OBJECTIVE: To investigate the association of omega-3 fatty acid blood levels with temporal changes in telomere length, an emerging marker of biological age. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of 608 ambulatory outpatients in California with stable coronary artery disease recruited from the Heart and Soul Study between September 2000 and December 2002 and followed up to January 2009 (median, 6.0 years; range, 5.0-8.1 years). MAIN OUTCOME MEASURES: We measured leukocyte telomere length at baseline and again after 5 years of follow-up. Multivariable linear and logistic regression models were used to investigate the association of baseline levels of omega-3 fatty acids (docosahexaenoic acid [DHA] and eicosapentaenoic acid [EPA]) with subsequent change in telomere length. RESULTS: Individuals in the lowest quartile of DHA+EPA experienced the fastest rate of telomere shortening (0.13 telomere-to-single-copy gene ratio [T/S] units over 5 years; 95% confidence interval [CI], 0.09-0.17), whereas those in the highest quartile experienced the slowest rate of telomere shortening (0.05 T/S units over 5 years; 95% CI, 0.02-0.08; P < .001 for linear trend across quartiles). Levels of DHA+EPA were associated with less telomere shortening before (unadjusted beta coefficient x 10(-3) = 0.06; 95% CI, 0.02-0.10) and after (adjusted beta coefficient x 10(-3) = 0.05; 95% CI, 0.01-0.08) sequential adjustment for established risk factors and potential confounders. Each 1-SD increase in DHA+EPA levels was associated with a 32% reduction in the odds of telomere shortening (adjusted odds ratio, 0.68; 95% CI, 0.47-0.98). CONCLUSION: Among this cohort of patients with coronary artery disease, there was an inverse relationship between baseline blood levels of marine omega-3 fatty acids and the rate of telomere shortening over 5 years.


Asunto(s)
Envejecimiento , Enfermedad de la Arteria Coronaria/genética , Ácidos Grasos Omega-3/sangre , Telómero/ultraestructura , Anciano , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/patología , Femenino , Aceites de Pescado , Humanos , Leucocitos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Estudios Prospectivos
16.
Planta Med ; 76(9): 869-75, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20112180

RESUMEN

Antioxidants such as vitamin E may act differently on skin cells depending on the age of the skin and the level of oxidative damage induced. The effects of alpha-tocopherol (ATF) on H(2)O(2)-induced DNA damage and telomere shortening of normal human skin fibroblast cells derived from young and old individual donors were determined. Fibroblasts were divided into five groups; untreated control, H(2)O(2)-induced oxidative stress, alpha-tocopherol treatment, and pre- and post-treatment with alpha-tocopherol for H(2)O(2)-induced oxidative stress. Our results showed that H(2)O(2)-induced oxidative stress increased DNA damage, shortened the telomere length and reduced the telomerase activity (p < 0.05) in fibroblasts obtained from young and old donors. Pre- and post-treatment with alpha-tocopherol protected against H(2)O(2)-induced DNA damage in fibroblasts obtained from young individuals (p = 0.005; p = 0.01, respectively). However, in fibroblasts obtained from old individuals, similar protective effects were only seen in cells pretreated with alpha-tocopherol (p = 0.05) but not in the post-treated cells. Protection against H(2)O(2)-induced telomere shortening was observed in fibroblasts obtained from both young and old donors which were pre-treated with alpha-tocopherol (p = 0.009; p = 0.008, respectively). However, similar protective effects against telomere shortening in fibroblasts obtained from both young and old donors were not observed in the post-treated fibroblasts. Protection against H(2)O(2)-induced telomerase activity loss was observed only in fibroblasts obtained from old donors which were pretreated with alpha-tocopherol (p = 0.04) but not in fibroblasts obtained from young donors. Similar protective effects against telomerase activity loss in fibroblasts obtained from both young and old donors were not observed in the post-treated fibroblasts. In conclusion, alpha-tocopherol protected against H(2)O(2)-induced telomere shortening by restoring the telomerase activity. It also modulated H(2)O(2)-induced DNA damage and this modulation was affected by donor age.


Asunto(s)
Senescencia Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Piel/efectos de los fármacos , Telómero/efectos de los fármacos , alfa-Tocoferol/farmacología , Factores de Edad , Senescencia Celular/genética , Esquema de Medicación , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Peróxido de Hidrógeno , Piel/metabolismo , Telomerasa/metabolismo , Telómero/ultraestructura
17.
Breast Cancer Res Treat ; 120(3): 769-75, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19543829

RESUMEN

Telomere dysfunction, which leads to genomic instability, is hypothesized to play a causal role in the development of breast cancer. However, the few epidemiologic studies that assessed the relationship between telomere length in blood cells and breast cancer risk have been inconsistent. We conducted two case-control studies to further understand the role of telomere length and breast cancer risk. Overall telomere lengths were measured by telomere quantitative fluorescent in situ hybridization (TQ-FISH) and telomere quantitative real-time PCR (TQ-PCR). The associations between telomere length in blood leukocytes and risk of breast cancer were examined in two breast cancer case-control studies that were conducted at Roswell Park Cancer Institute (RPCI) and Lombardi Comprehensive Cancer Center (LCCC). Using the 50th percentile value in controls as a cut point, women who had shorter telomere length were not at significantly increased risk of breast cancer compared with women who had longer telomere length in the RPCI study (odds ratio [OR] = 1.34, 95% confidence interval [CI] = 0.84-2.12), in the LCCC study (OR = 1.18, 95% CI = 0.73-1.91), or in the combined RPCI and LCCC studies (OR = 1.23, 95% CI = 0.89-1.71). There was no significant dose-response relationship across quartiles of telomere length and no significant difference when comparing women in the lowest to highest quartile of telomere length. Overall telomere length in blood leukocytes was not significantly associated with the risk of breast cancer.


Asunto(s)
Neoplasias de la Mama/epidemiología , Leucocitos/ultraestructura , Telómero/ultraestructura , Adulto , Anciano , Neoplasias de la Mama/sangre , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Femenino , Humanos , Hibridación Fluorescente in Situ , Menopausia , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Grupos Raciales , Factores de Riesgo , Fumar/epidemiología , Factores Socioeconómicos
18.
Br J Nutr ; 103(1): 107-13, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19671205

RESUMEN

Environmental and lifestyle factors that affect oxidative stress and inflammation may influence telomere length (TL). There are limited data to relate the effect of dietary components on TL. The present study examined the association between food groups and TL in a sample of elderly Chinese. In a sample of 2006 Chinese (976 men and 1030 women) aged 65 years and over, TL was measured by quantitative real-time PCR and daily intake of food groups was assessed by a validated FFQ. Linear regression and analysis of covariance were used to examine the association between food group intake and TL, with adjustment for demographic and lifestyle factors. In men, only Chinese tea consumption was significantly associated with TL after adjustment for demographics and lifestyle factors (P = 0.002). Mean difference in TL for those in the highest quartile of Chinese tea consumption (>3 cups/d or >750 ml/d) as compared with those in the lowest quartile of Chinese tea consumption (

Asunto(s)
, Telómero/ultraestructura , Anciano , Consumo de Bebidas Alcohólicas/epidemiología , Animales , Antropometría , China/epidemiología , Demografía , Dieta , Grasas de la Dieta , Escolaridad , Huevos , Conducta Alimentaria , Femenino , Frutas , Encuestas Epidemiológicas , Humanos , Esperanza de Vida , Estilo de Vida , Masculino , Carne , Aceites , Fumar/epidemiología , Verduras
19.
Neuroimmunomodulation ; 15(4-6): 251-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19047802

RESUMEN

Aging is associated with a natural dysregulation in immune functioning which may be amplified when it occurs in the context of chronic stress. Family dementia caregiving provides an excellent model to study the impact of chronic stress on immune functioning among older individuals. Empirical data suggest that the stress of caregiving dysregulates multiple components of innate and adaptive immunity. Elderly caregivers have poorer responses to vaccines, impaired control of latent viruses, exaggerated production of inflammatory mediators and accelerated cellular aging, compared to noncaregiving older adults. The chronic stress-induced immune dysregulation observed among older caregivers appears to be of sufficient magnitude to impact health. Furthermore, evidence suggests that chronic stress leads to premature aging of the immune system.


Asunto(s)
Envejecimiento/inmunología , Cuidadores/psicología , Estrés Psicológico/inmunología , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Envejecimiento/psicología , Envejecimiento Prematuro/etiología , Senescencia Celular , Enfermedad Crónica , Citocinas/fisiología , Femenino , Glucocorticoides/sangre , Glucocorticoides/fisiología , Herpesviridae/fisiología , Humanos , Inflamación/inmunología , Inflamación/fisiopatología , Interleucina-6/fisiología , Subgrupos Linfocitarios/inmunología , Masculino , Persona de Mediana Edad , Modelos Biológicos , FN-kappa B/fisiología , Psiconeuroinmunología , Telómero/ultraestructura , Vacunas/inmunología , Activación Viral , Cicatrización de Heridas/inmunología , Cicatrización de Heridas/fisiología
20.
Acupunct Electrother Res ; 32(1-2): 31-70, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18077937

RESUMEN

Using Bi-Digital O-Ring Test Resonance Phenomena between 2 identical substances, Omura, Y. succeeded in making the image of the outline of internal organs without use of standard imaging devices since 1982. When he imaged the outline of the stomach on the abdominal wall, a number of the lines came out from upper and lower parts of stomach wall. When the lines were followed, they were very close to the well-known stomach meridians. Subsequently, he found a method of localizing meridians and their corresponding acupuncture points as well as shapes and diameters accurately. At the anatomical location of ST 36 described in traditional textbooks, Omura, Y. found there is no acupuncture point. However, in the close vicinity, there is an acupuncture point which he named as true ST 36 in the mid 1980s, but it is generally known as Omura's ST 36. When the effects of the acupuncture on these 2 locations were compared, Omura's ST 36 (true ST 36) produced very significant well-known acupuncture beneficial effects including improved circulation and blood chemistry, while in the traditional ST 36, the effects were small. In this article, the anatomical relationship between these two acupuncture points, with a short distance of 0.6 approximately 1.5 cm between the centers of these locations, was described. In early 2000, Omura, Y. found Press Needle Stimulation of Omura's ST 36, using "Press-Release" procedure repeated 200 times, 4 times a day to cancer patients reduced high cancer cell telomere of 600-1500ng and high Oncogen C-fos Ab2 and Integrin alpha5beta1 of 100-700ng BDORT units to close to lyg (= 10(-24) g) BDORT units. In addition there was a significant reduction of Asbestos and Hg from cancer cells, while markedly reduced normal cell telomere of lyg was increased to optimally high amounts of 500-530ng BDORTunits. Thus, cancer cells can no longer divide and cancer activity is inhibited. The authors have successfully applied this method for a variety of cancers as well as for cardio-vascular diseases with hypertriglyceridemia, hyperglycemia, high L-homocystein, and CRP, high cardiac Troponim I & T, and some hypertension. These beneficial effects were accompanied by euphoria, & relaxation with increased alpha waves in EEG. Thus Omura's ST 36 stimulation is a safe, effective and highly desirable supplemental treatment. In addition to manual stimulation, similar beneficial effects can be induced by finger tip stmulation (without any needle) or with electroacupuncture stimulation, (+) Qi Gong energy stored paper and (+) solar energy stored paper which often resulted in significant clinical improvement.


Asunto(s)
Puntos de Acupuntura , Enfermedades Cardiovasculares/terapia , Neoplasias/patología , Telómero/patología , Acupuntura , Recuento de Células Sanguíneas , Glucemia/metabolismo , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/sangre , División Celular/fisiología , Electroacupuntura , Fundus Gástrico/fisiología , Homocisteína/sangre , Humanos , Hipertrigliceridemia/sangre , Hipertrigliceridemia/terapia , Rayos Láser , Lípidos/sangre , Miocardio/metabolismo , Telómero/ultraestructura , Troponina I/sangre , Ácido Úrico/sangre
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