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Environmental pollution can promote oxidative stress by exposing the body to various elements and substances that generate free radicals, such as lead and vanadium. These free radicals can negatively impact the respiratory, cardiovascular, immune, and neurological systems of vulnerable populations, including children, the elderly, and those with chronic diseases. To prevent or reduce oxidative stress, it is recommended to consume a balanced diet rich in natural antioxidants. These antioxidants can be found in various foods, especially in fruits and vegetables with intense colors, seeds, and spices. In recent decades, the effectiveness of consuming natural antioxidants such as resveratrol (found in wine), coffee, curcumin, garlic, vitamin C, vitamin E, and green tea has been demonstrated. These antioxidants have beneficial effects on the body, including the protection of cell membranes, regulation of gene expression associated with inflammation, prevention or reduction of endothelial damage, and the decrease or diminished severity of neurodegeneration, liver, and pulmonary disorders. Additionally, they stimulate the immune response. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introducción: las enfermedades cardiovasculares serán una de las principales causas de muerte en el país al 2020. Objetivo: determinar el efecto del consumo moderado del vino tinto sobre algunos marcadores de riesgo cardiovascular. Material y Métodos: se midió en vino capacidad antioxidante, antocianinas, polifenoles cuantificándose por cromatografía. Se seleccionaron 14 varones y 14 mujeres en 4 grupos de 7; dos grupos bebieron vino durante un mes, realizándoles análisis bioquímicos en condiciones basales, a los 15 y 30 días. Resultados: el vino presentó 226.9 mg/L antocianinas, C.I.50% del radical libre DPPH= 42.27 mg/ml; polifenoles totales = 1281.57 mg/L; cafeico = 11.82 mg/L, quercetina =9.40 mg/L y kaempherol =1.08 mg/L. En varones redujo significativamente en 10,19% glucosa, VLDL en 10,79% y el riesgo coronario 15,97% en varones y 36,5% en mujeres; incrementó significativamente 19,98% HDL en varones y 55,15% en mujeres. Conclusiones: el vino tinto aumentó HDL y redujo el índice de riesgo cardiovascular sobretodo en mujeres.

Copyright of Revista de Investigación en Salud VIVE is the property of Revista de Investigacion en Salud VIVE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Free radicals are compounds characterized by having an unpaired electron in their outer orbit, a condition that makes them highly reactive, i.e., they interact through diffusion-controlled reactions with proteins, lipids and nucleic acids. They have also been referred to as reactive oxygen species (ROS), reactive nitrogen species (RNS) or reactive sulfur species (RSS). In the human organism, they are mainly produced in the mitochondrial electron transport chain, where respiratory complexes I and III specifically participate and reduce oxygen by converting it into superoxide anion. Likewise, they can be formed through a wide variety of enzymatic and non-enzymatic reactions involving substances that are synthesized by cells or are ingested with food and some medicines. Human beings have an antioxidant system which is both enzymatic and non-enzymatic in nature and whose function is to protect the organism from the harmful action of free radicals. This system includes enzymes--such as catalase, superoxide dismutase, thioredoxin, etc.--and non-enzymatic compounds--such as glutathione, ferritin, myoglobin, etc. However, they are not efficient enough to protect it, so it is necessary to eat foods that contain substances with antioxidant properties whose protective action will depend on their chemical reactivity and their concentration. These antioxidant compounds are mainly found in fruits and vegetables, where polyphenols, flavonoids, carotenoids, vitamin C, vitamin E, etc. have been identified. A significant amount of evidence suggests that the intake of antioxidant substances protects the body from the damaging effect of free radicals, but when the oxidative action prevails over the antioxidant action, it can lead to oxidative stress, a condition that is closely linked to a wide variety of chronic non-communicable diseases including cancer, diabetes mellitus, obesity, psoriasis, atherosclerosis, among others. All this seems to indicate that the term "cellular redox steady state" more appropriately describes the constant adaptation to a situation of rapid chemical turnover and suggests that the substances involved in this process be designated as "biologically reactive species" due to the existence of harmful compounds such as hydrogen peroxide, peroxynitrite, etc., which are not--strictly speaking--free radicals but have toxic effects on cells. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Worldwide, approximately 50 million people have dementia, with Alzheimer disease (AD) being the most common type, accounting for 60%-70% of cases. Given its high incidence, it is imperative to design studies to expand our knowledge about its onset and development, and to develop early diagnosis strategies and/or possible treatments. One methodological strategy is the use of transgenic mouse models for the study of the factors involved in AD aetiology, which include oxidative stress and the immune response. Development: We searched the PubMed, Scopus, and Google Scholar databases for original articles and reviews published between 2013 and 2019. In this review, we address 2 factors that have been studied independently, oxidative stress and the immune response, in transgenic models of AD, and discuss the relationship between these factors and their impact on the loss of synaptic and structural plasticity, resulting in cognitive impairment. Conclusion: This review describes possible mechanisms by which oxidative stress and the immune response participate in the molecular, cellular, and behavioural effects of AD, observing a close relationship between these factors, which lead to cognitive impairment. Resumen: Introducción: En el mundo, alrededor de 50 millones de personas padecen demencia; la forma más común es la enfermedad de Alzheimer (EA), que representa el 60–70% de los casos. Dada su alta incidencia, se hace imperativo diseñar estudios que permitan ampliar el conocimiento sobre su aparición y desarrollo, para proponer diagnósticos tempranos y/o posibles tratamientos. Una de las estrategias metodológicas que se han desarrollado son los modelos transgénicos murinos para el estudio de los factores involucrados en su etiología, y entre ellos, el estrés oxidativo y la respuesta inmune. Desarrollo: Se realizó una búsqueda de artículos originales y revisiones en PubMed, Scopus y Google Scholar (2013–2019). En esta revisión abordamos dos factores que han sido estudiados de forma independiente: el estrés oxidativo y la respuesta inmune en modelos transgénicos para la EA, y se discute la relación que existe entre ellos y que impacta en la pérdida de la plasticidad sináptica y estructural, produciendo como efecto final el deterioro cognitivo. Conclusión: Esta revisión describe posibles mecanismos en donde participan el estrés oxidativo y la respuesta inmune sobre los efectos moleculares, celulares y conductuales en la EA, observando una estrecha relación entre estos elementos que conducen hacia el deterioro cognitivo.

Currently, many investigations have focused on the analysis of the antioxidant capacity of extracts from agro-industry wastes, thanks to their content in secondary metabolites such as phenols, flavonoids, anthocyanins, and carotenes, and their ability to react with free radicals and various oxygen reactive species. In this work, extracts of the Vaccinium meridionale fruit-shell was used to determine the antioxidant activity against singlet oxygen and free radicals 2,2-diphenyl-1-picrylhydracil (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS). The analysis of the total phenolic content (TPC) of the extract showed a significant content of phenolic groups (around 99.30 ± 3.15 mg of gallic acid/100 g of fresh fruit). On the other hand, the characterization by liquid chromatography (HPLC-DAD) showed the presence in the extract of six anthocyanins with the larger relative abundance (delphinidine-3-glucoside, delphinidine-3-arabinoside, cyanidine-3-glucoside, cyanidine-3- arabinoside, cyanidine-3-galactoside, and an unidentified anthocyanin). The percentage of deactivation of singlet oxygen was determined at different concentrations of the ethanolic extract, with a value of 51% at a concentration of 0.4 mg/mL, while the IC50 by the ABTS method was 311.5 µg/mL and by the DPPH method of 65.96 µg/mL. [ABSTRACT FROM AUTHOR]

Introducción: El estrés oxidativo ocurre cuando la producción de especies reactivas de oxígeno, supera la protección celular por parte de los antioxidantes. Este trabajo se centra en el estrés oxidativo inducido por la anestesia general, porque aumenta la tasa de complicaciones y retrasos en la recuperación. Objetivo: Actualizar sobre cómo los anestésicos utilizados para inducir y mantener la anestesia general, inciden en el estrés oxidativo que se genera durante el período transoperatorio. Desarrollo: Se realizó en una revisión de artículos sobre estrés oxidativo durante el acto anestésico quirúrgico. Los anestésicos endovenosos, por regla general, mantienen los marcadores de estrés oxidativo en valores próximos a la normalidad, actúan como moduladores del estrés oxidativo y la inflamación, bloquean los mecanismos de producción de especies reactivas del oxígeno. Los anestésicos inhalados modifican estos biomarcadores, cuando las intervenciones quirúrgicas sobrepasan las 2 horas. Los anestésicos generales provocan estrés oxidativo, que depende del tiempo de exposición y duración de la anestesia; aunque está demostrado que los intravenosos tienden a ser protectores, mientras que los volátiles lo desencadenan, pero solo en cirugías mayores, prolongadas. Conclusiones: El acto anestésico quirúrgico es un proceso complejo, en el cual confluyen numerosos factores que pueden provocar aumento de los niveles de especies reactivas al oxígeno, generan un cuadro de estrés oxidativo que puede afectar el resultado final de la cirugía, pero si se traza una estrategia que utilice anestésicos con acción protectora contra el estrés oxidativo se pueden obtener mejores resultados en el proceso quirúrgico.

Los radicales libres son compuestos caracterizados por tener un electrón desapareado en su orbital externo, condición que los torna altamente reactivos, es decir, tienen la propiedad de interactuar a través de reacciones controladas por difusión con proteínas, lípidos y ácidos nucleicos. También se les ha designado como especies reactivas de oxígeno (ERO), especies reactivas de nitrógeno (ERN) o especies reactivas de azufre (ERA). En el organismo humano se generan, principalmente, en la cadena transportadora de electrones mitocondrial, donde específicamente participan los complejos respiratorios I y III que tienen la propiedad de reducir al oxígeno y convertirlo en anión superóxido; así mismo, pueden formarse haciendo uso de una gran diversidad de reacciones enzimáticas y no enzimáticas en las que intervienen sustancias que la célula sintetiza o que se ingieren con los alimentos y algunos medicamentos. El ser humano dispone de un sistema antioxidante, que es de naturaleza enzimática y no enzimática, el cual tiene como función proteger al organismo de la acción nociva de los radicales libres; comprende enzimas —como catalasa, superóxido dismutasa, tiorredoxina, etc.— y compuestos no enzimáticos —como glutatión, ferritina, mioglobina, etc.—, pero no son lo suficientemente eficientes para protegerlo, por lo que es necesaria la ingesta de alimentos que contengan en su composición sustancias con propiedades antioxidantes cuya acción protectora dependerá de su reactividad química, así como de su concentración; estos compuestos antioxidantes se encuentran principalmente en las frutas y verduras, habiéndose identificado polifenoles, flavonoides, carotenoides, vitamina C, vitamina E, etc. Un número considerable de evidencias sugiere que la ingesta de sustancias antioxidantes protege al organismo del efecto dañino de los radicales libres, pero cuando prevalece la acción oxidante sobre la antioxidante puede conducirse al estrés oxidativo, condición que está estrechamente vinculada con una gran diversidad de enfermedades crónicas no transmisibles como cáncer, diabetes mellitus, obesidad, psoriasis, aterosclerosis, entre otras. Todo ello parece indicar que el término “estado estable redox celular” describe de manera apropiada la constante adaptación a una situación de rápido recambio químico, y sugiere que las sustancias implicadas en este proceso se designen como “especies biológicamente reactivas” en razón de la existencia de compuestos nocivos como el peróxido de hidrógeno, peroxinitrito, etc., que no son propiamente radicales libres, pero ejercen efectos dañinos a las células.

This study evaluated the antioxidant activity (AA) of cranberry juices available in supermarkets of San Luis Potosí, México, before and after storage at low temperature (4°C) by ABTS•, DPPH•, and FRAP methods. Twelve commercial juices were tested at the time of opening (D1) and 24 hours later (D2). The results were expressed as vitamin C equivalent antioxidant capacity (VCEAC) and percentages of free radical inhibition. The highest AA was recorded at 60 min, although it was different in the three methods. The AA decreased significantly in D2. Therefore, our study recommends the consumption of cranberry juice once the container is opened, to ensure the consumption of the antioxidant compounds associated with a beneficial effect on health. [ABSTRACT FROM AUTHOR]

Se evalúa la actividad antioxidante (AA) de jugos de arándano disponibles en los supermercados de San Luis Potosí, México, antes y después de su almacenamiento a baja temperatura (4 °C) mediante los métodos ABTS•, DPPH• y FRAP. Se analizan 12 jugos comerciales al abrirlos (D1) y 24 horas después (D2). Los resultados se expresaron como capacidad antioxidante equivalente a vitamina C (VCEAC) y porcentajes de inhibición de radicales libres. La mayor AA se registró a los 60 min, aunque fue diferente en los tres métodos. La AA disminuyó significativamente en D2. Por lo tanto, se recomienda el consumo de jugo de arándano una vez abierto el envase para garantizar el consumo de los compuestos antioxidantes asociados a un efecto benéfico para la salud.

Los antioxidantes son compuestos naturales o sintéticos capaces de prevenir o retardar el daño oxidativo, al contrarrestar radicales libres en biomoléculas expuestas a este tipo de estrés. La industria alimentaria, farmacéutica y cosmética ha optado por sustituir los ingredientes químicos por compuestos naturales, utilizando en gran cantidad compuestos obtenidos de plantas. Sin embargo, la mayor fuente de recursos naturales está en los microorganismos, debido a su gran diversidad y a los mecanismos metabólicos que desarrollan para adaptarse a zonas con ambientes no favorables para el desarrollo de la vida. Entre los microorganismos productores de compuestos útiles para los seres humanos que se incluyen en esta revisión se encuentran: hongos, bacterias y microalgas. Los microorganismos más explorados son los que habitan ambientes terrestres debido a la accesibilidad hacia los mismos; no obstante, el extenso ambiente marino también alberga una gran diversidad de organismos de los que se podrían obtener varios compuestos como carotenoides, flavonoides, fenoles o exopolisacáridos con aplicaciones cosméticas. En este artículo se presenta una revisión de 90 artículos publicados entre 2015 y 2020 con información relevante sobre los antioxidantes producidos por microorganismos acuáticos y terrestres con uso potencial en cosméticos, con el fin de proporcionar información significativa sobre alternativas a antioxidantes sintetizados artificialmente y obtenidos de fuentes vegetales.

La presencia de especies reactivas de oxígeno generan daños y estrés oxidativo, al haber producción y eliminación de estas especies en el organismo se presentan situaciones patológicas y de envejecimiento, estas especies pueden ser controladas mediante agentes reguladores como lo son sustancias antioxidantes de bajo peso molecular, lo cual conlleva a generar un protocolo de una metodología de evaluación antioxidante que sea fácilmente reproducible bajo las condiciones del laboratorio de análisis instrumental de la Universidad CES. ORAC es un método ampliamente utilizado para analizar la capacidad antioxidante, pero es un método altamente sensible y posee factores que puede presentar alteraciones si no se tienen estándares bien estipulados generando fluctuaciones en la lectura o proporcionando datos que no sean válidos. Por lo tanto, se estandarizará el método bajo los parámetros estipulados por las Buenas Prácticas de Fabricación (PAF), obteniendo resultados satisfactorios en términos de especificidad para el análisis de compuestos antioxidantes hidrosolubles, robustez de ±10% para el análisis antioxidante de L-Ácido Ascórbico, precisión y exactitud, se realizarán más ensayos para obtener resultados óptimos de linealidad en términos de test de linealidad y proporcionalidad.

Currently, many investigations have focused on the analysis of the antioxidant capacity of extracts from agro-industry wastes, thanks to their content in secondary metabolites such as phenols, flavonoids, anthocyanins, and carotenes, and their ability to react with free radicals and various oxygen reactive species. In this work, extracts of the Vaccinium meridionale fruit-shell was used to determine the antioxidant activity against singlet oxygen and free radicals 2,2-diphenyl-1-picrylhydracil (DPPH) and 2,2'-azino--bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS). The analysis of the total phenolic content (TPC) of the extract showed a significant content of phenolic groups (around 99.30 ± 3.15 mg of gallic acid/100 g of fresh fruit). On the other hand, the characterization by liquid chromatography (HPLC-DAD) showed the presence in the extract of six anthocyanins with the larger relative abundance (delphinidine-3-glucoside, delphinidine-3-arabinoside, cyanidine-3-glucoside, cyanidine-3- arabinoside, cyanidine-3-galactoside, and an unidentified anthocyanin). The percentage of deactivation of singlet oxygen was determined at different concentrations of the ethanolic extract, with a value of 51% at a concentration of 0.4 mg/mL, while the IC50 by the ABTS method was 311.5 µg/mL and by the DPPH method of 65.96 µg/mL. [ABSTRACT FROM AUTHOR]

The department of La Guajira (Colombia) presents a great diversity of plant species, among these, halophilic and psamophilic species such as Ipomoea pes-caprae (L.) R.Br., which is distributed in the department coastal area. It was unknown whether I. pes-caprae produces phenols in concentrations high, enough under La Guajira's environmental conditions, to consider its use; therefore, the aim of this research was to establish the influence of weather on total phenols production and antioxidant potential of foliar extracts. Leaf tissue samples were taken during one year and subjected to methanol extraction. To establish total phenols concentration, Folin-Ciocalteau method was used and correlated with rains and monthly temperature. Extracts percentage of inhibition on DPPH radical was also estimated. Results showed that phenols content varied throughout one year, with February 2019 showing the highest concentration (18.41%), coinciding with a low rainfall and lower temperature period. On the other hand, antioxidant activity of extracts was 83.79%. It was concluded that temperature partially affects the total phenols concentration, while rains did not have significant effects; in addition, this study verifies the possibility of using I. pes-caprae as a low-cost source of substances with antioxidant activity and constitutes a basis for future research aimed at the evaluation and use of other Convolvulaceae species present in La Guajira. [ABSTRACT FROM AUTHOR]

Introduction. Periodontal therapy aims to reduce infectious and inflammatory states in order to stop the progressive destruction of tissues. In recent years, the role of coenzyme Q10 (CoQ10) as an endogenous antioxidant has been studied in its role in the treatment of periodontitis as well as an adjuvant to effectively suppress inflammation. Objective. To systematically assess the available evidence for better outcomes of conventional treatment with intrasulcular application of Coq10. Methodology. An electronic search of the MEDLINE and COCHRANE LIBRARY databases using the terms MESH "Periodontitis", "Periodontal disease" and "Coenzyme Q10" was performed. We searched for clinical trials that considered scaling and root planning interventions with and without subsequent intrasulcular application of Coq10; results are listed for plaque index, pocket depth and clinical insertion level. A total of 36 studies were found but only four met the eligibility requirements and therefore were included in the review. Results. After processing the data in EPIDAT 3.1 software the results obtained from the comparison of means between the groups were for plaque index p < 0.05, bag depth p > 0.05 and loss of clinical insertion p > 0.05. Conclusions. The intrasulcular application of CoQ10 as a complement to scaling and root planning proved to be effective in the treatment of chronic periodontitis to reduce plaque index. [ABSTRACT FROM AUTHOR]

Antioxidants are natural or synthetic compounds capable of preventing or delaying oxidative damage, by counteracting free radicals in biomolecules exposed to this type of stress. The food, pharmaceutical and cosmetic industry has replaced chemical ingredients with natural compounds, using substances obtained from plants. However, the greatest source of natural resources is in microorganisms, due to their great diversity and the metabolic mechanisms they have developed to adapt to areas with unfavorable environments. The microorganisms that produce compounds useful for humans that are included in the review are: fungi, bacteria, and microalgae. The most explored microorganisms are those that inhabit terrestrial environments due to their accessibility, however the extensive marine environment also harbors a great diversity of organisms from which several compounds such as carotenoids, flavonoids, phenols or exapolysaccharides to applied in cosmetic industry. This article presents a review of 90 articles published between 2015 and 2020 with relevant information about antioxidants produced by aquatic and terrestrial microorganisms with potential use in cosmetics, to provide relevant information about alternatives to artificially or plants synthetized antioxidants. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas is the property of Universidad de Santiago de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Nutrición Clínica y Dietética Hospitalaria is the property of Sociedad Espanola de Dietetica y Ciencias de la Alimentacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most of the pathologic components of oxidative stress of cardiovascular diseases are closely related with diregulation of metabolism of reactive species of oxygen, which favor the appearance of the so called oxidative stress. The oxidation of low density lipoproteins, endothelial dysfunction and inflammatory processes are mediated in some way by cellular production of the reactive oxygen species. This review is conducted aimed at revising the latest findings that explain the influence of free radicals in the origin of atherosclerosis. It is concluded that oxygen is the main source of free radical formation whose action is determinant for the genesis of atherosclerosis. The increase of oxidative stress favors atherothrombatic phases: platelet adhesion and aggregation, cell proliferation, lipid and protein perioxidation, irreversible damage in DNA and mitochondrial membrane and inestabilzation/desestabilization of the plaque.

Mosses are used by many cultures to treat different diseases, probably due to their bioactive compounds, some of which may have antioxidant activity. This research evaluated the antioxidant activity (AA) of the species Breutelia subdisticha (Hampe) A. Jaeger, Leptodontium viticulosoides (P. Beauv.) Wijk & Margad. and Pylaisia falcata Schimp., from dichloromethane and ethanolic extracts, using the 2,2-diphenyl-1-picrylhydracil (DPPH*) and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS*+) methods. Inhibitory concentration (IC50) and relative antioxidant activity (% AAR) were determined from the extracts obtained using the Soxhlet technique, with subsequent statistical analysis (ANOVA and Tukey's post-hoc). The ethanolic extracts exhibited higher antioxidant capacity than those of dichloromethane. By the DPPH* method the ethanolic extracts showed a relative antioxidant activity with respect to ascorbic acid for L. viticulosoides 3.06, B. subdisticha 177.00 and P. falcata 141.66. Using ABTS*+ method, ethanolic extracts showed a relative antioxidant activity with respect to ascorbic acid for L. viticulosoides 1.75, B. subdisticha 139.17 and P. falcata 120.22. In conclusion, L. viticulosoides exhibited the best antioxidant activity, therefore, we propose to continue with its research, in order to achieve a pharmacological application from a natural source. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas is the property of Universidad de Santiago de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The loss of functional capacities, aging and death are inherent to all living matter due to metabolism and other factors causing the formation of substances which damage irreversibly cell structure components. With the objective of updating about the last findings which explain the role of oxidative stress on cell aging, a bibliographic review is done. It is concluded that oxygen which is necessary for cell viability and other exogenous substances show toxicity since they lead to the formation of free radicals whose action is the main cause of aging. In addition, the administration of anti- oxidants is very important to prevent aging and improve the population´s quality of life.

Introduction: Background: it is well known that moderate or vigorous physical exercise produces an increase in free radicals. Aim: the aims of this study were to observe changes in malondialdehyde and antioxidant vitamins after a maximum incremental test, and to relate malondialdehyde and antioxidant vitamin values to performance parameters. Methods: eighty-four male athletes participated in this study. Participants performed a maximum incremental test until exhaustion on a treadmill. Malondialdehyde in plasma and antioxidant vitamins in plasma and erythrocytes were determined before and after the test. Results: in plasma, there was a decrease in malondialdehyde after the test. In erythrocytes, results showed increases in vitamin C and decreases in vitamin E after the test. Maximal oxygen uptake values were associated positively with vitamin C and negatively with malondialdehyde levels before the test. On the other hand, maximal oxygen uptake, total test time, and total test distance were positively related to the malondialdehyde values obtained after the test. Conclusions: a maximum incremental test did not produce any changes in plasma vitamins in athletes. However, it increased the levels of vitamin C in erythrocytes and decreased malondialdehyde values in plasma and vitamin E in erythrocytes. The levels of malondialdehyde, vitamin C and vitamin E were related to performance parameters. These results may be linked to the adaptation of antioxidant systems due to regular training. [ABSTRACT FROM AUTHOR]

Objectives: To determine the phytochemical composition and evaluate the antioxidant activity of the hydroalcoholic extracts of S. haematospermum; P. niruri; P. tenellus; E. serpens. Methodology: The phytochemical composition was analyzed by thin layer chromatography and the antioxidant activity was observed qualitatively by autographic assay. Total phenols were quantified with the Folin-Ciocalteu method and total flavonoids with the aluminum complexation reaction. To determine the antioxidant activity, the discoloration techniques of the free radical DPPH• (2,2-diphenyl-1-picrilhydracil) and of the cation radical ABTS•+ (2,2-Azino-bis-3-ethylbenzothiazolin-6-sulfonic acid) and the reducing power of the iron (III) cation. Results: The phytochemical study showed the presence of bioactive metabolites in all species. The total phenol content ranged from: 627.71 ± 1.45 to 369.8 ± 52.6 mg EAG / g sample and total flavonoids was 12.2 ± 0.1 to 4.5 ± 0.3 mg Q / g sample. The species S. haematospermum and P. tenellus presented higher content of polyphenols. The antioxidant activity tests allowed recognizing that S. haematospermum and P. tenellus have a capacity for greater inhibition of the tested free radicals and the hydroalcoholic extracts S. haematospermum and P. niruri showed greater reducing power. [ABSTRACT FROM AUTHOR]

Copyright of Revista Habanera de Ciencias Médicas is the property of Universidad de Ciencias Medicas de La Habana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently, many investigations have focused on the analysis of the antioxidant capacity of extracts from agro-industry wastes, thanks to their content in secondary metabolites such as phenols, flavonoids, anthocyanins, and carotenes, and their ability to react with free radicals and various oxygen reactive species. In this work, extracts of the Vaccinium meridionale fruit-shell was used to determine the antioxidant activity against singlet oxygen and free radicals 2,2-diphenyl-1-picrylhydracil (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS). The analysis of the total phenolic content (TPC) of the extract showed a significant content of phenolic groups (around 99.30 ± 3.15 mg of gallic acid/100 g of fresh fruit). On the other hand, the characterization by liquid chromatography (HPLC-DAD) showed the presence in the extract of six anthocyanins with the larger relative abundance (delphinidine-3-glucoside, delphinidine-3-arabinoside, cyanidine-3-glucoside, cyanidine-3-arabinoside, cyanidine-3-galactoside, and an unidentified anthocyanin). The percentage of deactivation of singlet oxygen was determined at different concentrations of the ethanolic extract, with a value of 51% at a concentration of 0.4 mg/mL, while the IC50 by the ABTS method was 311.5 µg/mL and by the DPPH method of 65.96 µg/mL. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effect of two antioxidants (Trolox and Crocin) added to the freezing extender on the cryopreservation of Pelibuey ram semen. Semen samples were pooled, split and frozen into 3 treatments: T1: Trolox 1mM; T2: Crocin 1mM; TT: Control (without antioxidant). Total motility (MT), progressive motility (PM), sperm viability, mitochondrial activity, acrosomes integrity, and plasma membrane integrity of the tail (Host) were assessed at 0 h (thawed), and at 6 hours at 37 °C. The results were analyzed with ANOVA, followed by Tukey's comparison test. At 0 h and 6 h, no differences were found (P> 0.05) in all the parameters evaluated between treatments, however, from 0 to 6 hours, the MT was similar in the T1 and T2, but not in the TT (P <0.01), on the contrary, acrosome integrity in the three treatments was similar (P>0.05). MP, viability, mitochondrial activity, and Host dropped through time in a similar way in the three treatments. The addition of the antioxidants Trolox and Crocin at 1 mM to the freezing extender allows maintaining the total motility and acrosome integrity during 6 h of incubation at 37 °C. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archivos Latinoamericanos de Nutrición is the property of Sociedad Latinoamericana de Nutricion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Las especies estudiadas en este trabajo fueron Sapium haematospermum Müll. Arg. (Euphorbiaceae) y Baillonia amabilis Bocq. (Verbenaceae), las cuales crecen en cercanías de los ríos Paraná y Paraguay. Estas especies se encuentran formando parte de los árboles cultivados en jardines y veredas de las zonas urbanas de la provincia del Chaco y se emplean en medicina popular. Los objetivos del trabajo fueron determinar aspectos farmacognósticos y principales grupos de metabolitos de las especies Baillonia amabilis y Sapium haematospermum, y evaluar la capacidad antioxidante de sus extractos. Los ensayos farmacognósticos se hicieron según Farmacopea Argentina, Séptima Edición. La detección de grupos de metabolitos secundarios se hizo a partir de un extracto etanólico de cada especie o sus fracciones, mediante reacciones colorimétricas y cromatografía en capa fina. El contenido de fenoles totales se determinó por un método colorimétrico con el reactivo Folin-Ciocalteu y el contenido de flavonoides totales por el método de complejación con nitrato de aluminio. La actividad antioxidante se ensayó con los radicales DPPH° y ABTS°+. Los ensayos fitoquímicos permitieron detectar metabolitos secundarios en la fracción A (con etanol: flavonoides, taninos) y fracción B (con cloroformo y ácido: esteroides y triterpenos) de ambas especies. El contenido de fenoles totales fue mayor para las tinturas que para infusión y decocción, en tintura de Sapium haematospermum el valor fue 627,71 ± 1,45 mg EAG/g muestra y en tintura de Baillonia amabilis fue 771,81 ± 50,16 mg EAG/g muestra. Las tinturas también presentaron mayor contenido de flavonoides y actividad antioxidante que las infusiones y decocciones en ambas especies. Para ambas especies se determinaron metabolitos secundarios como fenoles, taninos, flavonoides, esteroides y cardenólidos. Las tinturas mostraron mayor contenido de polifenoles y capacidad antioxidante. Estos resultados aportan conocimiento científico para estas especies de uso popular en el Chaco.

El maíz (Zea mays L.) constituye junto con el trigo y el arroz uno de los cereales importantes del mundo, suministra elementos nutritivos tanto a los seres humanos como a los animales y es materia prima básica para la industria alimenticia. Las variedades de color morado o negro además de presentar nutrientes contienen antioxidantes naturales que ayudan a reducir el riesgo de enfermedades cardiacas, respiratorias y a prevenir enfermedades degenerativas como el cáncer. El objetivo del presente estudio fue determinar el efecto del procesamiento en el contenido de compuestos y la actividad antioxidante del grano y raquis de las variedades de maíz: INIAP-199 y Sangre de Cristo. En estado crudo, el grano de INIAP-199 presentó el mayor contenido de fenoles (276.24 mg.100 g-1) y antocianinas totales (241.97 mg.100 g-1), zinc (3.72 mg.100 g-1) y carotenoides (281.42 ug.100 g-1). Igualmente, en el raquis de esta variedad se registró un mayor contenido de flavonoides (210.73 mg.100 g-1), taninos (100.54 mg.100 g-1) y ácido ascórbico (503.87 mg.100 g-1). El extracto del raquis de INIAP-199 presentó un mayor poder antioxidante reductor férrico (1.92 mg.ml-1), este valor superó al extracto del grano (2.90 mg.ml-1). En los extractos del raquis y grano de la variedad Sangre de Cristo se registró una menor capacidad para reducir el ión férrico (6.59 y 6.92 mg.ml-1), lo cual podría guardar relación con la menor concentración de compuestos fenólicos en sus extractos. En general, el proceso de remojo afectó en menor grado a la concentración de compuestos con capacidad antioxidante del grano, el efecto contrario se determinó con el perlado, lo que hace suponer que los componentes con las mencionadas propiedades se concentran en el pericarpio del grano.

Oxidative stress is the result of an imbalance between free radicals and antioxidants. Under normal physiological conditions, free radicals are involved in reproductive events such as cell cycle activation, ovulation and luteolysis. However, when an overproduction of free radicals surpasses antioxidant capacity, oxidative damage, reproductive anomalies and diminished fertility occur. Supplementation with antioxidants prevents oxidative damage and can be incorporated into reproductive management to improve fertility in females. Selection of the preovulatory follicle, ovulation, fertilization, embryo development and formation of the corpus luteum occur during the periconceptional period. This is a dynamic period and the events are susceptible to oxidative stress damage. Therefore, the objective of this review is to discuss the effect of oxidative stress on reproductive events during the periconceptional period, as well as to address antioxidant supplementation during this period. [ABSTRACT FROM AUTHOR]

The present study was conducted to examine the antioxidant potential of African mistletoe (Viscum album L.) as alternative feed additive for Laying Pullets. Fresh African mistletoe leaves were harvested from cocoa trees and shade dried to constant weight. The leaves were grounded and were designated as mistletoe leaf meal (AMLM). Total of sixty ISA Brown pullets at 18 weeks old were randomly allocated to four dietary treatment consisting of 5 replicates with 3 birds per replicate, when egg production was 4% in a completely randomized design. The birds were fed layer ration and dietary mistletoe supplement as treatments T1 (basal diet + 0% AMLM), T2 (basal diet + 2% AMLM), T3 (basal diet + 4%AMLM) and T4 (basal diet + 6%AMLM) during 16 week feeding trial. At 8th week and end of the feeding trial, blood samples were collected through the Jugular vein into a sample bottle from all birds for serum oxidative indicator assay; malondialdehyde (mMDA/mgprotein), total antioxidant activity (mmol/litre), glutathione peroxidase (GPx, μgGSH/ min/mgprotein), superoxide dismutase (SOD, U/min/mg protein) and catalase (nmH2O2/min/ mg protein) using standard procedures. The result obtained revealed that at 8 weeks of lay, lipid peroxidation in laying pullets were significantly (P<0.05) lowered by mistletoe supplementation while total antioxidant activity of significantly (P<0.05) increased with mistletoe inclusion. Pullets fed 6% mistletoe supplemented diets significantly (P<0.05) enhanced catalase and glutathione peroxidase activity. Total antioxidant activity and all antioxidant enzymes of laying pullets increased, as laying cycle progresses, while lipid peroxidation reduced. This could signify that laying pullets have better antioxidative stability at 16 weeks of lay compared than pullets at 8weeks of lay. It can be concluded that African mistletoe leaf meal inclusion in laying pullets diet enhance antioxidant profile in pullets. [ABSTRACT FROM AUTHOR]

The Brazil nut is an important product from the Amazonian region and its productive chain is an income source for local communities. The effect of combinations of packaging atmospheres (loose or vacuum-packed) and storage temperatures (4±1 °C or 24±2 °C) on the tendency of lipid radical formation and on volatiles was investigated for the first time in shelled Brazil nut kernels. It was observed that refrigeration, whether combined with lose packing or vacuum packing, was effective to reduce the tendency for lipid radical formation, as detected by spin-trapping electron spin resonance (ESR) spectroscopy, as well as peroxides, conjugated dienes and 3-octen-2-one. However, the combination of refrigeration with vacuum packing, even using low-density polyethylene (LDPE) pouches with a high oxygen transmission rate (OTR), also reduced the formation of hexanal, which is a major off-flavor volatile, and thus should be recommended for the storage of Brazil nut kernels for the studied period. [ABSTRACT FROM AUTHOR]

En la actualidad, el cáncer representa una epidemia que puede ser considerada como un problema de salud pública. Es por esto que el desarrollo farmacológico ha tomado un auge en pro de mejorar las tasas de sobrevida y remisión. No obstante, esto ha sido oscurecido por la toxicidad de estas terapias. La cardiotoxicidad es un efecto adverso conocido de la terapia oncológica, que limita en muchas ocasiones una adecuada administración de regímenes con disminución de la eficacia; por esto, el entendimiento de las bases fisiopatológicas y moleculares son esenciales para determinar medidas preventivas y terapéuticas que permitan una disminución en la incidencia de la toxicidad, sin influir en la efectividad de la terapia oncológica. A continuación se realiza una revisión de los efectos adversos de la quimioterapia en el sistema cardiaco, incluyendo desde sus bases moleculares hasta sus implicaciones clínicas.

Birth asphyxia is one of the principal causes of early neonatal death. In survivors it may evolve to hypoxic-ischaemic encephalopathy and major long-term neurological morbidity. Prolonged and intense asphyxia will lead to energy exhaustion in tissues exclusively dependent on aerobic metabolism, such as the central nervous system. Energy deficit leads to ATP-dependent pumps blockage, with the subsequent loss of neuronal transmembrane potential. The most sensitive areas of the brain will die due to necrosis. In more resistant areas, neuronal hyper-excitability, massive entrance of ionic calcium, activation of NO-synthase, free radical generation, and alteration in mitochondrial metabolism will lead to a secondary energy failure and programmed neuronal death by means of the activation of the caspase pathways. A third phase has recently been described that includes persistent inflammation and epigenetic changes that would lead to a blockage of oligodendrocyte maturation, alteration of neurogenesis, axonal maturation, and synaptogenesis. In this scenario, oxidative stress plays a critical role causing direct damage to the central nervous system and activating metabolic cascades leading to apoptosis and inflammation. Moderate whole body hypothermia to preserve energy stores and to reduce the formation of oxygen reactive species attenuates the mechanisms that lead to the amplification of cerebral damage upon resuscitation. The combination of hypothermia with coadjuvant therapies may contribute to improve the prognosis. Resumen: La asfixia intraparto es una de las causas más frecuentes de muerte neonatal precoz pero también puede, en los supervivientes, evolucionar a una encefalopatía hipóxico-isquémica responsable de una elevada morbilidad neurológica. La presencia de episodios de hipoxia-isquemia prolongados conduce a un rápido agotamiento energético en los tejidos exclusivamente dependientes del metabolismo aeróbico, como el sistema nervioso central. El déficit energético conlleva una paralización de las bombas ATP-dependientes y subsiguiente pérdida del potencial neuronal transmembrana. La población neuronal de las regiones más sensibles del SNC mueren por necrosis, mientras que en otras áreas se produce una hiperexcitabilidad neuronal con entrada masiva de calcio iónico, activación de NO-sintasa, generación de radicales libres que alteran el funcionamiento mitocondrial, provocando un fallo energético secundario y muerte neuronal por apoptosis. Recientemente se ha propuesto una tercera fase en la que factores como la inflamación persistente y los cambios epigenéticos causarían un bloqueo de la maduración de los oligodendrocitos, alteración de la neurogénesis, del crecimiento axonal y de la sinaptogénesis. En este contexto, el estrés oxidativo va a tener un papel protagonista como responsable tanto en causar daño directo al SNC como en activar cascadas metabólicas conducentes a la apoptosis e inflamación. La hipotermia moderada precoz, al preservar las reservas energéticas y disminuir la formación de especies reactivas de oxígeno, atenuará el daño cerebral posreanimación. La combinación de la hipotermia con terapias coadyuvantes para modular el estrés oxidativo podría contribuir a mejorar el pronóstico.

Antraciclinas como la doxorrubicina, así como anticuerpos monoclonales, como el trastuzumab, y agentes alquilantes, como la ciclofosfamida, son compuestos muy útiles como quimioterapia citotóxica al reducir en forma significativa la mortalidad relacionada con el cáncer. Sin embargo, su potencial cardiotoxicidad es un efecto adverso mayor que puede presentarse en cualquier momento de su administración o posterior a la misma, en especial cuando se usan combinados. La toxicidad cardiovascular por doxorrubicina suele ser dependiente de dosis e irreversible, mientras la ocasionada por trastuzumab no lo es. Se han encontrado cambios electrocardiográficos habituales durante la administración de quimioterapia, independiente de la dosis acumulada; a estos cambios agudos se les ha dado poca importancia, aunque pueden suceder hasta en el 40% de los pacientes. A pesar de la aparición documentada de arritmias tanto en humanos como en modelos animales, la muerte súbita cardiaca durante o inmediatamente después de la infusión de quimioterapia no está bien descrita. Se presenta el caso de un adulto joven sin antecedentes cardiovasculares, con linfoma no-Hodgkin y corazón con imagen ecocardiográfica muy sugestiva de infiltración linfomatosa del ventrículo izquierdo, quien desarrolla alteraciones del ritmo cardiaco que condicionan muerte súbita tras la infusión endovenosa lenta de doxorrubicina y trastuzumab.

La diabetes es un trastorno metabólico que se ha incrementado en Latinoamérica y Venezuela en la última década. Ejerce una influencia considerable en la morbimortalidad de las enfermedades cardiovasculares debido al desequilibrio hidrocarbonado y a los pacientes fuera de los objetivos de la Asociación americana de diabetes 2012, con factores de riesgo como hipertensión y dislipidemia. Es, igualmente, un estado de estrés oxidativo en el que hay un desequilibrio entre la formación excesiva y la eliminación insuficiente de moléculas altamente reactivas, como las especies reactivas de oxígeno y las de nitrógeno. El estrés oxidativo desempeña un papel importante en el desarrollo de complicaciones de la diabetes debido a la actividad oxidativa excesiva. La disfunción endotelial se define como alteraciones que afectan la síntesis, liberación, difusión o degradación de los factores sintetizados por el endotelio. El mecanismo intrínseco que impulsa a las células endoteliales para cambiar su fenotipo fisiológico es un estado de activación, conocido erróneamente como disfunción en la capacidad de expresar los sistemas enzimáticos de producción de oxígeno. Los fármacos que modulan la vía de la incretina (GLP-1 y los inhibidores de la DPP-4) se caracterizan por la baja incidencia de su efecto hipoglucemiante, fenómeno que aumenta su seguridad. Estudios recientes con GLP-1 demuestran su capacidad para revertir el estrés oxidativo producido por la hiperglucemia, la hipoglucemia y la transición de esta última y la primera.

The loss of functional capacities, aging and death are inherent to all living matter due to metabolism and other factors causing the formation of substances which damage irreversibly cell structure components. With the objective of updating about the last findings which explain the role of oxidative stress on cell aging, a bibliographic review is done. It is concluded that oxygen which is necessary for cell viability and other exogenous substances show toxicity since they lead to the formation of free radicals whose action is the main cause of aging. In addition, the administration of anti- oxidants is very important to prevent aging and improve the population´s quality of life. [ABSTRACT FROM AUTHOR]