Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
1.
Rev. chil. nutr ; 50(6)dic. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550795

RESUMO

Oxidative stress (OS) occurs when the antioxidant defense system is overwhelmed by the predominance of reactive oxygen species (ROS) and pro-oxidant factors. Several diseases such as hypertension, insulin resistance, type 2 diabetes mellitus and neurodegenerative diseases are characterized by chronic OS. Physical exercise constitutes an affordable tool to prevent or ameliorate these conditions. However, during physical activity, acute ROS are produced inducing an activation in peroxisome proliferator activated receptor-Gamma Coactivator-1alpha (PGC-1α), and nuclear factor erythroid-2 related factor 2 (Nrf2), PGC-1α/Nrf2 pathway. This signaling pathway facilitates interaction with antioxidant response elements (ARE), thereby initiating an upregulation in the expression of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and mitochondrial biogenesis. In both cases, whether involving healthy animals or individuals engaged in physical exercise, supplementation with antioxidant scavengers leads to a reduction in the expression and activity of PGC-1α, SOD, CAT, and GPX across various tissues, which is not observed with indirect antioxidants. The preventive role of physical exercise against chronic OS is avoided when executed in conjunction with supplementation of scavenger antioxidants. However, similar to exercise, the indirect antioxidant apigenin can activate the PGC1-α/Nrf2 signaling pathway. Here, we summarize evidence supporting apigenin as a non-nutritional supplement that could enhance the adaptive effects of exercise, improving the endogenous antioxidant defense. Therefore, apigenin could be an interesting supplement to enhance the endogenous antioxidant adaptation induced by exercise in healthy subjects, but also to improve the effectiveness of exercise to prevent oxidative stress-associated diseases.


El estrés oxidativo (OS) ocurre cuando el sistema de defensa antioxidante es sobrepasado por el predominio de especies reactivas de oxígeno (ROS) y factores prooxidantes. Varias enfermedades como la hipertensión, la resistencia a la insulina, la diabetes mellitus tipo 2 y enfermedades neurodegenerativas se caracterizan por un OS crónico. El ejercicio físico constituye una herramienta asequible para prevenir o mejorar estas enfermedades. Sin embargo, durante la actividad física, se producen ROS agudas que inducen una activación en la vía PGC-1α/Nrf2. Esta vía de señalización facilita la interacción con los elementos de respuesta antioxidante (ARE), iniciando así una regulación que permite la expresión de enzimas antioxidantes, incluidas SOD, CAT, GPX y biogénesis mitocondrial. En ambos casos, ya sea que se trate de animales sanos o de individuos que practican ejercicio físico, la suplementación con antioxidantes "scavengers" conduce a una reducción en la expresión y actividad de PGC-1α, SOD, CAT y GPX en varios tejidos, lo que no se observa con antioxidantes "indirectos". El papel preventivo del ejercicio físico contra el OS crónico se atenúa cuando se realiza en conjunto con la suplementación de antioxidantes "scavengers". Sin embargo, de manera similar al ejercicio, la apigenina es un antioxidante "indirecto" que puede activar la vía de señalización PGC1-α/Nrf2. Aquí, resumimos la evidencia que respalda a apigenina como un suplemento no-nutricional que podría mejorar los efectos adaptativos del ejercicio, mejorando la defensa antioxidante endógena de sujetos sanos que no tienen suficiente tiempo para hacer ejercicio.

2.
Neurologia (Engl Ed) ; 38(7): 486-494, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37659839

RESUMO

INTRODUCTION: Mir-146a-5p has been widely recognized as a critical regulatory element in the immune response. However, recent studies have shown that miR-146a-5p may also be involved in the development of Alzheimer disease (AD). Regrettably, the related mechanisms are poorly understood. Here, we investigated the effects of miR-146a in mice models and SH-SY5Y cells treated with amyloid ß (Aß)1-42. METHODS: To create a model of AD, SH-SY5Y cells were treated with Aß1-42 and mice received intracerebroventricular injections of Aß1-42. Then, the transcriptional levels of miR-146a were estimated by real-time PCR. We transiently transfected the miR-146a-5p mimic/inhibitor into cells and mice to study the role of miR-146a. The role of signaling pathways including p38 and reactive oxygen species (ROS) was studied by using specific inhibitors. Aß and amyloid-beta precursor protein (APP)levels were measured by immunoblotting. Furthermore, Aß expression was analyzed by immunofluorescence and histochemical examinations. RESULTS: Aß1-42-stimulated SH-SY5Y cells displayed increased transcriptional levels of miR-146a and APP. Moreover, the p38 MAPK signaling pathway and ROS production were activated upon stimulation with a miR-146a-5p mimic. However, treatment with a miR-146a-5p inhibitor decreased the levels of APP, ROS, and p-p38 MAPK. A similar phenomenon was also observed in the animals treated with Aß1-42, in which miR-146a upregulation increased the expression of Aß, p-p38, and ROS, while the inhibition of miR-146a had the opposite effect. This suggests that miR-146a increases Aß deposition and ROS accumulation via the p-p38 signaling pathway. CONCLUSIONS: Our research demonstrates that miR-146a-5pa increases Aß deposition by triggering oxidative stress through activation of MAPK signaling.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , MicroRNAs , Neuroblastoma , Humanos , Animais , Camundongos , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Espécies Reativas de Oxigênio , Estresse Oxidativo , Precursor de Proteína beta-Amiloide , MicroRNAs/genética
3.
Rev. int. androl. (Internet) ; 21(3): 1-9, jul.-sep. 2023. graf
Artigo em Inglês | IBECS | ID: ibc-222352

RESUMO

Background: Hormonal changes alter the physiological level of ROS and cause oxidative stress in the cell. As estimated, hormonal deficiencies, environmental and ideological factors make up about 25% of male infertility. Pathogenic reactive oxygen species (ROS) is a chief cause of unexplained infertility. Limited studies exist on the effects of testosterone on human sperm culture. Therefore, in the current study, the effect of different doses of testosterone on sperm parameters and chromatin quality was investigated. Materials and methods: Semen samples from 15 normospermic and 15 asthenospermic patients were prepared by swim up method, and then were divided into four groups by exposing to different concentrations of testosterone (1, 10, and 100nM) for 45min. Samples without any intervention were considered as control group. All samples were washed twice. Sperm parameters and chromatin protamination were assessed in each group and the remains were frozen. After two weeks, all tests were repeated for sperm thawed. Also, the MSOM technique was used to determine the sperm morphology of class 1. Results: Although sperm parameters were not show any significant differences in normospermic and asthenospermic samples exposed to different concentrations of testosterone before and after freezing, chromatin protamination was significantly decreased in the normospermic samples exposed to 10nM of testosterone before freezing (p<0.006), as well as 1 and 10nM of testosterone after freezing compared to control samples (p=0.001 and p=0.0009, respectively). (AU)


Antecedentes: Los cambios hormonales alteran el nivel fisiológico de las especies reactivas de oxígeno (reactive oxygen species [ROS]) patógenas y provocan estrés oxidativo en la célula. Según estimaciones, las deficiencias hormonales, los factores ambientales y los ideológicos constituyen alrededor del 25% de la infertilidad masculina. Las ROS son una causa principal de infertilidad inexplicable. Existen estudios limitados sobre los efectos de la testosterona en el cultivo de esperma humano. Por lo tanto, en el estudio actual se ha investigado el efecto de diferentes dosis de testosterona sobre los parámetros del esperma y la calidad de la cromatina. Materiales y métodos: Se prepararon muestras de semen de 15 pacientes normospérmicos y 15 astenospérmicos mediante el método swim up, y luego se dividieron en cuatro grupos exponiéndolos a diferentes concentraciones de testosterona (1, 10 y 100nM) durante 45min. Las muestras sin ninguna intervención se consideraron como grupo control. Todas las muestras se lavaron dos veces. En cada grupo se evaluaron los parámetros espermáticos y la protaminación de la cromatina, y los restos se congelaron. Dos semanas después se repitieron todas las pruebas de esperma descongelado. Asimismo, se utilizó la técnica MSOM para determinar la morfología espermática de clase 1. Resultados: Aunque los parámetros espermáticos no mostraron diferencias significativas en las muestras normospérmicas y astenospérmicas expuestas a diferentes concentraciones de testosterona antes y después de la congelación, la protaminación de la cromatina disminuyó significativamente en las muestras normospérmicas expuestas a 10nM de testosterona antes de la congelación (p<0,006), así como a 1 y 10nM de testosterona después de la congelación, en comparación con las muestras de control (p=0,001 y p=0,0009, respectivamente). (AU)


Assuntos
Humanos , Testosterona , Cromatina , Astenozoospermia , Espécies Reativas de Oxigênio , Irã (Geográfico)
4.
Neurología (Barc., Ed. impr.) ; 38(7): 486-494, Sept. 2023. graf
Artigo em Inglês | IBECS | ID: ibc-224782

RESUMO

Introduction: Mir-146a-5p has been widely recognized as a critical regulatory element in the immune response. However, recent studies have shown that miR-146a-5p may also be involved in the development of Alzheimer disease (AD). Regrettably, the related mechanisms are poorly understood. Here, we investigated the effects of miR-146a in mice models and SH-SY5Y cells treated with amyloid β (Aβ)1–42. Methods: To create a model of AD, SH-SY5Y cells were treated with Aβ1–42 and mice received intracerebroventricular injections of Aβ1–42. Then, the transcriptional levels of miR-146a were estimated by real-time PCR. We transiently transfected the miR-146a-5p mimic/inhibitor into cells and mice to study the role of miR-146a. The role of signaling pathways including p38 and reactive oxygen species (ROS) was studied by using specific inhibitors. Aβ and amyloid-beta precursor protein (APP)levels were measured by immunoblotting. Furthermore, Aβ expression was analyzed by immunofluorescence and histochemical examinations. Results: Aβ1–42-stimulated SH-SY5Y cells displayed increased transcriptional levels of miR-146a and APP. Moreover, the p38 MAPK signaling pathway and ROS production were activated upon stimulation with a miR-146a-5p mimic. However, treatment with a miR-146a-5p inhibitor decreased the levels of APP, ROS, and p-p38 MAPK. A similar phenomenon was also observed in the animals treated with Aβ1–42, in which miR-146a upregulation increased the expression of Aβ, p-p38, and ROS, while the inhibition of miR-146a had the opposite effect. This suggests that miR-146a increases Aβ deposition and ROS accumulation via the p-p38 signaling pathway. Conclusions: Our research demonstrates that miR-146a-5pa increases Aβ deposition by triggering oxidative stress through activation of MAPK signaling.(AU)


Introducción: miR-146a-5p es un elemento regulador clave en la respuesta inmune. Sin embargo, estudios recientes sugieren que miR-146a-5p también está involucrado en el desarrollo de la enfermedad de Alzheimer (EA), aunque aún no se conoce con exactitud el mecanismo por el que esto sucede. Analizamos los efectos de miR-146a en un modelo animal y en células SH-SY5Y expuestas a β-amiloide (Aβ)1-42. Métodos: Tratamos células SH-SY5Y con Aβ1-42 e inyectamos Aβ1-42 en los ventrículos cerebrales de ratones para generar un modelo celular y otro animal de EA. Estimamos los niveles transcripcionales de miR-146a mediante PCR en tiempo real. Al mismo tiempo, transfectamos temporalmente las células y los ratones con imitador/inhibidor de miR-146a-5p para evaluar el papel de miR-146a. Estudiamos el papel de algunas vías de señalización, como la de p38, y los niveles de especies reactivas de oxígeno (ERO) con inhibidores específicos. Los niveles de Aβ y de proteína precursora amiloidea (APP) se determinaron con inmunoblot. También se analizó la expresión de Aβ mediante inmunofluorescencia y análisis histoquímico. Resultados: Las células SH-SY5Y expuestas a Aβ1-42 mostraron altos niveles transcripcionales de miR-146a y APP. La vía de señalización p-38 MAPK y la producción de EROs se activaron al utilizar un imitador de miR-146a-5p. Sin embargo, el bloqueo de miR-146a-5p con un inhibidor redujo los niveles de APP, EROs y p-p38 MAPK. Se observó un fenómeno similar en los ratones tratados con Aβ1-42: la sobrerregulación de miR-146a aumentó la expresión de Aβ, p-p38 y EROs, mientras que la inhibición de miR-146a tuvo el efecto contrario. Esto sugiere que miR-146a está involucrado en el aumento de acumulación de Aβ y de producción de EROs por medio de la vía de señalización p-p38. Conclusiones: Nuestro estudio muestra que miR146a-5p aumenta la acumulación de Aβ al promover el estrés oxidativo a través de la activación de la vía de señalización MAPK.(AU)


Assuntos
Humanos , Doença de Alzheimer/complicações , Disfunção Cognitiva , Estresse Oxidativo , Sistema de Sinalização das MAP Quinases , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides , Neurologia , Doenças do Sistema Nervoso , Espécies Reativas de Oxigênio
5.
Rev Int Androl ; 21(3): 100352, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37244225

RESUMO

BACKGROUND: Hormonal changes alter the physiological level of ROS and cause oxidative stress in the cell. As estimated, hormonal deficiencies, environmental and ideological factors make up about 25% of male infertility. Pathogenic reactive oxygen species (ROS) is a chief cause of unexplained infertility. Limited studies exist on the effects of testosterone on human sperm culture. Therefore, in the current study, the effect of different doses of testosterone on sperm parameters and chromatin quality was investigated. MATERIALS AND METHODS: Semen samples from 15 normospermic and 15 asthenospermic patients were prepared by swim up method, and then were divided into four groups by exposing to different concentrations of testosterone (1, 10, and 100nM) for 45min. Samples without any intervention were considered as control group. All samples were washed twice. Sperm parameters and chromatin protamination were assessed in each group and the remains were frozen. After two weeks, all tests were repeated for sperm thawed. Also, the MSOM technique was used to determine the sperm morphology of class 1. RESULTS: Although sperm parameters were not show any significant differences in normospermic and asthenospermic samples exposed to different concentrations of testosterone before and after freezing, chromatin protamination was significantly decreased in the normospermic samples exposed to 10nM of testosterone before freezing (p<0.006), as well as 1 and 10nM of testosterone after freezing compared to control samples (p=0.001 and p=0.0009, respectively). Similarly, chromatin protamination in the asthenospermic samples was significantly decreased at concentration of 1nM of testosterone before and after freezing (p=0.0014 and p=0.0004, respectively), and at concentration of 10nM of testosterone before and after freezing (p=0.0009, p=0.0007) compared to control samples. CONCLUSION: Using a low dose of testosterone in the sperm culture medium, has positive effects on chromatin quality.


Assuntos
Astenozoospermia , Sêmen , Humanos , Masculino , Cromatina , Testosterona/farmacologia , Espécies Reativas de Oxigênio , Criopreservação/métodos , Espermatozoides/fisiologia , Astenozoospermia/tratamento farmacológico
6.
Horiz. meÌüd. (Impresa) ; 23(2)abr. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1440192

RESUMO

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.


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.

7.
An. R. Acad. Nac. Farm. (Internet) ; 88(número extraordinario): 288-300, diciembre 2022. ilus
Artigo em Espanhol | IBECS | ID: ibc-225770

RESUMO

El estrés oxidativo, alteración de la homeostasis REDOX en células y tejidos con un incremento de los niveles de especies reactivas de oxígeno (ROS), es un mecanismo patogénico común a múltiples patologías como las enfermedades cardiovasculares, los desórdenes neurodegenerativos, la inflamación y el cáncer, razón por la cual ha existido una investigación intensa en las últimas décadas sobre los posibles efectos protectores de las terapias antioxidantes en estas enfermedades. No obstante, la señalización REDOX juega, por otra parte, un papel crítico en la homeostasis y supervivencia celular, y las ROS son producidas en pequeñas cantidades durante la función celular normal. Las investigaciones llevadas a cabo en nuestro grupo han estado enfocadas al estudio del estrés oxidativo como factor patogénico clave en la disfunción endotelial en la obesidad y en otros estados de resistencia a la insulina. La disfunción endotelial subyace a las complicaciones vasculares de la diabetes y la obesidad, y representa un fenotipo endotelial mal adaptado con alteración de la función vasodilatadora, angiogénica y de barrera del endotelio, lo que conduce a un estado vasoconstrictor, proinflamatorio y protrombótico de la pared vascular. Debido a su capacidad de inhabilitar el óxido nítrico (NO), las ROS son en parte responsables de la disfunción endotelial. Por otra parte, nuestros estudios durante estos años han permitido caracterizar el papel clave de ROS como el H2O2 en la función endotelial de arterias de resistencia renales y coronarias, y su participación en la función vascular mediante la modulación de canales iónicos y enzimas implicados en vías de señalización de la pared arterial. (AU)


Oxidative stress, impairment of REDOX homeostasis in cells and tissues leading to increased levels of reactive oxygen species (ROS), is a pathogenic mechanism underlying numerous pathologies including cardiovascular diseases, cancer, neurodegenerative disorders and inflammation. Therefore, there has been an intensive investigation during the last decades on the potential protective effects of antioxidant therapies on these disorders. Nevertheless, REDOX signaling plays a critical role in homeostasis and cell survival, and ROS are produced in small amount during normal cell function. Investigations carried out in our group during the last decade have been focused on the study of oxidative stress as a key pathogenic factor in endothelial and vascular dysfunction of resistance arteries in obesity and other insulin resistant states. Endothelial dysfunction underlies vascular complications of diabetes and obesity, and represents a maladapted endothelial phenotype consisting of impaired vasodilatation, angiogenesis and barrier function leading to a vasoconstrictor, pro-inflammatory and pro-thrombotic state of the vascular wall. ROS are involved in endothelial dysfunction since they reduce bioavailability of nitric oxide (NO). On the other hand, our investigations have provided evidence for a key role of ROS such as hydrogen peroxide (H2O2) in the endothelial function of healthy coronary and renal resistance arteries, and its involvement in vascular function through modulation of ion channels and enzymes involved in signalling pathways of the arterial wall. (AU)


Assuntos
Humanos , Espécies Reativas de Oxigênio , Endotélio Vascular , Estresse Oxidativo , Obesidade
8.
Arq. ciências saúde UNIPAR ; 26(3): 1313-1324, set-dez. 2022.
Artigo em Português | LILACS | ID: biblio-1414506

RESUMO

A manipulação de oócitos inclusos em folículos ovarianos pré-antrais (MOIFOPA) vem sendo estudada pensando na perspectiva futura de aplicação direta na reprodução humana, principalmente para mulheres que sofrem de doenças ou que precisam passar por tratamentos que interferem na função ovariana. Nesse contexto, o objetivo deste trabalho é revisar aspectos relacionados com a biotécnica de MOIFOPA e a importância dos antioxidantes no cultivo in vitro de folículos pré-antrais. Foi realizada uma pesquisa na base de dados PubMed, buscando artigos sobre a biotécnica, principalmente relacionados com a necessidade do uso de antioxidantes no cultivo. A grande maioria dos estudos sobre a biotécnica utilizam como modelo experimental os folículos ovarianos de diferentes espécies de animais. A MOIFOPA compreende o isolamento e o resgate de folículos ovarianos pré-antrais provenientes de ovários, seguido da conservação através da técnica de resfriamento ou congelação e o cultivo folicular in vitro, a fim de promover o crescimento, a maturação e a fecundação in vitro (FIV) dos oócitos inclusos nesses folículos, maximizando o potencial reprodutivo feminino e diminuindo a atresia folicular que acontece in vivo. Um aspecto que pode interferir no sucesso do cultivo in vitro de folículos ovarianos pré-antrais é a produção em excesso de espécies reativas de oxigênio (EROs). Os ácidos ascórbico e alfa lipóico vem demonstrando resultados interessantes para reduzir os efeitos que as EROs causam sobre os folículos ovarianos pré-antrais cultivados in vitro.


The manipulation of oocytes included in preantral ovarian follicles (MOEPF) has been studied considering the future perspective of direct application in human reproduction, especially for women who suffer from diseases or who need to undergo treatments that interfere with ovarian function. In this context, the objective of this paper is to review aspects related to the biotechnology of MOIFOPA and the importance of antioxidants. A search was carried out in the PubMed database, searching for articles on biotechnology, mainly related to the need to use antioxidants in cultivation. The vast majority of studies on biotechnology use ovarian follicles from different species of animals as an experimental model. MOIFOPA comprises the isolation and rescue of preantral ovarian follicles from ovaries, followed by conservation through the cooling or freezing technique and in vitro follicular cultivation, in order to promote growth, maturation and in vitro fertilization ( IVF) of the oocytes included in these follicles, maximizing the female reproductive potential and decreasing the follicular atresia that occurs in vivo. One aspect that may interfere with the success of in vitro culture of preantral ovarian follicles is the excess production of reactive oxygen species (ROS). Ascorbic and alpha lipoic acids have shown interesting results in reducing the effects that ROS cause on in vitro cultured preantral ovarian follicles.


manipulación de ovocitos incluidos en folículos ováricos preantrales (MOIFOPA) se ha estudiado con la perspectiva futura de su aplicación directa en la reproducción humana, especialmente en mujeres que padecen enfermedades o que necesitan someterse a tratamientos que interfieren en la función ovárica. En este contexto, el objetivo de este trabajo es revisar los aspectos relacionados con la biotécnica de MOIFOPA y la importancia de los antioxidantes en el cultivo in vitro de los folículos pré-antrais. Se realizó una investigación en la base de datos PubMed, buscando artículos sobre la biotecnología, principalmente relacionados con la necesidad del uso de antioxidantes en el cultivo. La mayoría de los estudios sobre biotecnología utilizan como modelo experimental los folículos ováricos de diferentes especies de animales. El MOIFOPA incluye el aislamiento y rescate de los folículos ováricos preantrales de los ovarios, seguido de su conservación mediante la técnica de enfriamiento o congelación y el cultivo folicular in vitro, con el fin de promover el crecimiento, la maduración y la fecundación in vitro (FIV) de los ovocitos incluidos en estos folículos, maximizando el potencial reproductivo femenino y disminuyendo la atresia folicular que se produce in vivo. Un aspecto que puede interferir en el éxito del cultivo in vitro de folículos ováricos preantrales es la producción excesiva de especies reactivas de oxígeno (ROS). El ácido ascórbico y el ácido alfa lipoico han mostrado resultados interesantes para reducir los efectos que causan las ERO en los folículos ováricos preantrales cultivados in vitro.


Assuntos
Oócitos , Folículo Ovariano , Antioxidantes , Ácido Ascórbico , Biotecnologia , Fertilização In Vitro , Estresse Oxidativo , Atresia Folicular , Lipoproteínas
9.
Rev. colomb. ciencias quim. farm ; 51(1)ene.-abr. 2022.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1535813

RESUMO

SUMMARY Background and aims: Mycobacterium tuberculosis (Mtb), the main causative agent of human tuberculosis (TB), remains as a serious public health problem. The innate immune response following Mtb infection plays a crucial role in preventing the onset of active TB and limiting its spread. Since phagocytes-derived reactive oxygen/nitrogen species (ROS/RNS) during the oxidative burst can fight Mtb, we hypothesized that the use of antioxidants could increase the host's susceptibility to Mtb/TB. In that way, we investigated the effects of the nitroxide Tempol, an antioxidant with superoxide dismutase-like activity, on the response of neutrophils against Mtb. Methods: Human blood-derived neutrophils were isolated from healthy volunteers and incubated with Mtb (H37Ra) at different multiplicities of infection (MOIs), in the absence or presence of Tempol. The levels of ROS in neutrophils were evaluated using the cytochrome C reduction assay (extracellular O2 •-) and luminol-(total intracellular and extracellular ROS) and isoluminol-(extracellular ROS) amplified chemiluminescence assay. The killing assay (two-step protocol) checked the mycobactericidal capacity of neutrophils, as calculated the phagocytosis (K p ) and intracellular killing (Kk) rates. Results: The levels of ROS and killing capacity in Mtb-stimulated neutrophils were significantly decreased by 450 µM Tempol (p < 0.05). Interestingly, Tempol decreased the k k of neutrophils, but did not affect their kp, demonstrating that a putative diminution in ROS levels, ultimately, affected the intracellular killing of Mtb. Conclusion: This study provides insights regarding the role of antioxidants on the neutrophil response toward Mtb, so that our findings deserve to be considered regarding further studies and clinical implications.


Contextualización y objetivos: Mycobacterium tuberculosis (Mtb), el principal agente causal de la tuberculosis humana (TB), es un grave problema de salud pública. La respuesta inmune innata desencadenada en la infección por Mtb juega un papel crucial en la prevención de la aparición de la tuberculosis activa y en la limitación de su propagación. Dado que las especies reactivas de oxígeno/nitrógeno derivadas de los fagocitos (ERO/ERN) durante el burst oxidativo pueden combatir la infección pulmonar por Mtb, planteamos la hipótesis de que el uso de antioxidantes podría aumentar la susceptibilidad del huésped humano hacia Mtb/TB. De esa manera, investigamos los efectos del nitróxido Tempol, un antioxidante con actividad similar a la superóxido dismutasa, sobre la respuesta de los neutrófilos contra Mtb. Métodos: se aislaron neutrófilos derivados de sangre humana de voluntarios sanos y se incubaron con Mtb (H37Ra) en diferentes multiplicidades de infección (MOI), en ausencia o presencia de Tempol. Los niveles de ERO en neutrófilos se evaluaron mediante el ensayo de la reducción del citocromo C (O2'- extracelular) y el ensayo de quimioluminiscencia, amplificada mediante el uso de luminol (ERO total, intracelular y extracelular) e isoluminol (ERO extracelular). La prueba de actividad microbicida (protocolo de dos pasos) verificó la capacidad micobactericida de los neutrófilos, calculando las tasas de fagocitosis (Kp) y muerte intracelular (Kk). Resultados: los niveles de ERO y la capacidad micobactericida en neutrófilos estimulados con Mtb disminuyeron significativamente en los grupos tratados con 450 µM de Tempol (p < 0,05). Curiosamente, Tempol disminuyó la tasa de muerte intracelular (Kk) en neutrófilos, pero no tuvo ningún efecto sobre la tasa de fagocitosis (Kp), lo que demuestra que una supuesta disminución en los niveles de ERO, en última instancia, afectó la destrucción intracelular de Mtb. Conclusión: este estudio proporciona información sobre el papel de los antioxidantes en la respuesta de los neutrófilos hacia Mtb, por lo que nuestros hallazgos merecen ser considerados con respecto a más estudios e implicaciones clínicas.


Contextualização e objetivos: Mycobacterium tuberculosis (Mtb), principal agente causal da tuberculose humana (TB), é um grave problema de saúde pública. A resposta imune inata desencadeada pela infecção por Mtb desempenha um papel crucial na prevenção do aparecimento da tuberculose ativa e na limitação de sua disseminação. Como as espécies reativas de oxigênio/nitrogênio derivadas de fagó-citos (ERO/ERN) durante a burst oxidativa podem combater a infecção pulmonar por Mtb, hipotetizamos que o uso de antioxidantes poderia aumentar a suscetibilidade do hospedeiro humano ao Mtb/TB. Assim, investigamos os efeitos do nitróxido de Tempol, um antioxidante com atividade semelhante a superóxido dismutase, na resposta de neutrófilos contra o Mtb. Métodos: neutrófilos derivados de sangue humano foram isolados de voluntários saudáveis e incubados com Mtb(H37Ra) em diferentes multiplicidades de infecção (MOI), na ausência ou presença de Tempol. Os níveis de ERO em neutrófilos foram avaliados por ensaio de depleção de citocromo C (O2•- extracelular) e ensaio de quimioluminescência, amplificado com luminol (ERO total, intracelular e extracelular) e isoluminol (ERO extracelular). O teste de atividade microbicida (protocolo de duas etapas) verificou a capacidade micobactericida dos neutrófilos, calculando as taxas de fagocitose (Kp) e morte intracelular (Kk). Resultados: os níveis de ERO e a capacidade micobactericida em neutrófilos estimulados por Mtb diminuíram significativamente nos grupos tratados com Tempol 450 µM (p < 0,05). Curiosamente, Tempol diminuiu a taxa de morte intracelular (Kk) em neutrófilos, mas não teve efeito sobre a taxa de fagocitose (Kp), mostrando que uma diminuição putativa nos níveis de ERO afetou a morte intracelular de Mtb. Conclusão: este estudo fornece informações sobre o papel dos antioxidantes na resposta dos neutrófilos ao Mtb, portanto, nossos achados merecem consideração para estudos adicionais e implicações clínicas.

10.
Neurologia (Engl Ed) ; 37(4): 277-286, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34531154

RESUMO

INTRODUCTION: Overpopulation and industrial growth result in an increase in air pollution, mainly due to suspended particulate matter and the formation of ozone. Repeated exposure to low doses of ozone, such as on a day with high air pollution levels, results in a state of chronic oxidative stress, causing the loss of dendritic spines, alterations in cerebral plasticity and in learning and memory mechanisms, and neuronal death and a loss of brain repair capacity. This has a direct impact on human health, increasing the incidence of chronic and degenerative diseases. DEVELOPMENT: We performed a search of the PubMed, Scopus, and Google Scholar databases for original articles and reviews published between 2000 and 2018 and addressing the main consequences of ozone exposure on synaptic plasticity, information processing in cognitive processes, and the alterations that may lead to the development of neurodegenerative diseases. CONCLUSIONS: This review describes one of the pathophysiological mechanisms of the effect of repeated exposure to low doses of ozone, which causes loss of synaptic plasticity by producing a state of chronic oxidative stress. This brain function is key to both information processing and the generation of structural changes in neuronal populations. We also address the effect of chronic ozone exposure on brain tissue and the close relationship between ozone pollution and the appearance and progression of neurodegenerative diseases.


Assuntos
Poluição do Ar , Doenças Neurodegenerativas , Ozônio , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Humanos , Doenças Neurodegenerativas/induzido quimicamente , Plasticidade Neuronal , Estresse Oxidativo , Ozônio/efeitos adversos
11.
NOVA publ. cient ; 20(3): [17], 2022 enero-junio. gráficos, mapas, tablas e ilustraciones
Artigo em Espanhol | LILACS | ID: biblio-1397023

RESUMO

Resumen Introducción. Las células madre mesenquimales han generado interés en la ingeniería de tejidos, debido a sus propiedades proliferativas y capacidad de reparación de tejidos, sin embargo, para un trasplante exitoso, es necesario aumentar el número de células mediante un cultivo in-vitro. Durante este proceso la capacidad proliferativa disminuye, provocando cambios en la morfología y funcionalidad celular y afectando la viabilidad del cultivo, este estado se conoce como senescencia celular y como posibles causales, se ha considerado el estrés oxidativo y la falta de factores de crecimiento. Objetivos: Evaluar el efecto de FGF-2 sobre la senescencia de un cultivo de células madre mesenquimales aisladas de gelatina de Wharton y su papel en la regulación del estrés oxidativo. Metodología. Se añadieron dosis de 3,5 y 7,5 ng de FGF-2 al cultivo. Durante los pasajes 5 y 7, se estimó tanto la senescencia celular como la presencia de ROS (especies reactivas de oxígeno). Resultados.Se obtuvo en el pasaje 5, una diferencia significativa del 99,5% entre el control (+) con respecto a los tratamientos con FGF-2, sin embargo, en el pasaje 7 se observó un aumento en la producción de la enzima ß-galactosidasa y cambios morfológicos, confirmando un estado senescente en el cultivo en todos los tratamientos evaluados. Conclusión. Las dosis utilizadas en este estudio contribuyeron positivamente a disminuir el proceso senescente en el cultivo celular, además se determinó, que el FGF-2 puede prolongar el tiempo de cultivo, retardando parcialmente la concentración de especies reactivas de oxígeno


AbstractIntroduction. Mesenchymal stem cells have been generated interest in tissue engineering, due to their proliferative properties and tissue repair capacity, however, for a successful transplant process, it is necessary to increase the number of cells in a culture expansion process. During this process the proliferative capacity is limited, causing changes in cell morphology and functionality affecting the viability of the culture, this state is known as cell senescence. Oxidative stress and deregulation of growth factors are considered as reasons. Aims. To evaluate the effect of FGF-2 on the senescence of a mesenchymal stem cells culture isolated from Wharton ́s jelly and its role in the regulation of oxidative stress. Methodology: 3,5 and 7,5 ng doses of FGF-2 were added to the culture medium from passage 2, then the senescence of the culture was evaluated and the presence of reactive oxygen species was determined during passages 5 and 7. Results. We observed that in passage 5, there is a significant difference 99.5% between the control (+) concerning the FGF-2 treatments, however, in passage 7, an increase in the production of the enzyme ß-galactosidase was observed and changes in morphology such as: increase in size and elongated shape of the cell, confirming a senescent state on the culture in all the treatments evaluated. Conclusion. The doses used in this study contributed positively to decrease this process in a cell culture, also, the FGF- 2 can prolong the cultivation time, partially decreasing the concentration of reactive oxygen species


Assuntos
Humanos , Células-Tronco Mesenquimais , Fator 2 de Crescimento de Fibroblastos , Peptídeos e Proteínas de Sinalização Intercelular , Geleia de Wharton
12.
Bol. latinoam. Caribe plantas med. aromát ; 20(4): 416-426, jul. 2021. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1369485

RESUMO

Reactive oxygen species are implicated in multiple pathological conditions including erectile dysfunction. This study evaluated the in vitro and in vivo antioxidant potential of the methanolic extracts of Inula glomerata and Salacia kraussii. The plant materials were pulverized and extracted with methanol. The phytochemical analysis, ability of the crude extracts to scavenge free radicals (ABTS, DPPH, NO.) in vitroas well as the total phenolic and flavonoid contents was investigated. In vivo, antioxidant potentials of the crude extracts (50/250 mg/kg body weight) were determined in an erectile dysfunction rat model. The phytochemical analysis revealed that both plants contain flavonoids, tannins, terpenoids, and alkaloids. The crude extracts at varying degree of efficiency, scavenged ABTS and DPPH radicals. The crude extracts at low concentrations (50 mg/kg b.w) significantly (p<0.05) diminished the level of malondialdehyde, augmented catalase activities and elevated glutathione levels. However, SOD activities were significantly boosted in a dose-dependent manner by the crude extracts. Therefore, I. glomerataand S. kraussiipossess antioxidant properties, hence, can serve as a therapeutic modality in the treatment of oxidative stress-induced erectile dysfunction.


Las especies reactivas de oxígeno están implicadas en múltiples condiciones patológicas, incluyendo la disfunción eréctil. Este estudio evaluó el potencial antioxidante in vitro e in vivo de extractos metanólicos de Inula glomeratay Salacia kraussii. Los materiales vegetales fueron pulverizados y extraídos con metanol. A estos extractos crudos se les llevó a cabo el análisis fitoquímico junto con el contenido total de fenólicos y flavonoides, así como se les investigó la capacidad in vitro para atrapar radicales (ABTS, DPPH, NO.). Los potenciales antioxidantes in vivo de los extractos crudos (50/250 mg/kg de peso corporal) se determinaron en un modelo en ratas con disfunción eréctil. El análisis fitoquímico reveló que ambas plantas contuvieron flavonoides, taninos, terpenoides y alcaloides. Los extractos crudos con un grado variable de eficiencia, atraparon a los radicales ABTS y DPPH. Los extractos crudos a bajas concentraciones (50 mg/kg p.c) significativamente (p<0.05) disminuyeron el nivel de malondialdehído, aumentaron las actividades de catalasa y elevaron los niveles de glutatión. Sin embargo, las actividades de SOD por los extractos crudos fueron significativamente dosis-dependientes. Así, los extractos de I. glomeratay S. kraussii mostraron propiedades antioxidantes, y por lo tanto, podrían servir como una alternativa terapéutica en el tratamiento de disfunción eréctil inducida por estrés oxidativo.


Assuntos
Animais , Ratos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Inula/química , Salacia/química , Antioxidantes/farmacologia , Antioxidantes/química , Ácidos Sulfônicos/metabolismo , Flavonoides/análise , Espécies Reativas de Oxigênio , Ratos Sprague-Dawley , Estresse Oxidativo/efeitos dos fármacos , Asteraceae/química , Celastraceae/química , Benzotiazóis/metabolismo , Compostos Fenólicos/análise , Compostos Fitoquímicos/análise , Óxido Nítrico/metabolismo
13.
Neurologia (Engl Ed) ; 2021 Mar 11.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33715884

RESUMO

INTRODUCTION: Mir-146a-5p has been widely recognized as a critical regulatory element in the immune response. However, recent studies have shown that miR-146a-5p may also be involved in the development of Alzheimer disease (AD). Regrettably, the related mechanisms are poorly understood. Here, we investigated the effects of miR-146a in mice models and SH-SY5Y cells treated with amyloid ß (Aß)1-42. METHODS: To create a model of AD, SH-SY5Y cells were treated with Aß1-42 and mice received intracerebroventricular injections of Aß1-42. Then, the transcriptional levels of miR-146a were estimated by real-time PCR. We transiently transfected the miR-146a-5p mimic/inhibitor into cells and mice to study the role of miR-146a. The role of signaling pathways including p38 and reactive oxygen species (ROS) was studied by using specific inhibitors. Aß and amyloid-beta precursor protein (APP)levels were measured by immunoblotting. Furthermore, Aß expression was analyzed by immunofluorescence and histochemical examinations. RESULTS: Aß1-42-stimulated SH-SY5Y cells displayed increased transcriptional levels of miR-146a and APP. Moreover, the p38 MAPK signaling pathway and ROS production were activated upon stimulation with a miR-146a-5p mimic. However, treatment with a miR-146a-5p inhibitor decreased the levels of APP, ROS, and p-p38 MAPK. A similar phenomenon was also observed in the animals treated with Aß1-42, in which miR-146a upregulation increased the expression of Aß, p-p38, and ROS, while the inhibition of miR-146a had the opposite effect. This suggests that miR-146a increases Aß deposition and ROS accumulation via the p-p38 signaling pathway. CONCLUSIONS: Our research demonstrates that miR-146a-5pa increases Aß deposition by triggering oxidative stress through activation of MAPK signaling.

14.
CES odontol ; 33(2): 112-127, jul.-dic. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1285755

RESUMO

Resumen Durante la periodontitis se liberan mediadores inflamatorios y especies reactivas de oxígeno (ROS), cuando se incrementan producen estrés oxidativo. Este artículo de revisión describe el papel que desempeñan las ROS y el estrés oxidativo en el desarrollo y evolución de la inflamación y lesión tisular durante la periodontitis. Para ello, se realizó una revisión de la literatura en bases de datos como PubMed, ScienceDirect, Wiley Online Library, Springer, Plos one, Nature, Sage journals, Hindawi y Taylor & Francis Online, mostrando los siguientes resultados: las ROS producen daño directo e indirecto a los tejidos periodontales. Los daños directos in- cluyen peroxidación de lípidos, oxidación de proteínas y del ADN. Los daños indirectos involucran la regulación de las vías de señalización del factor de trans- cripción nuclear kappa B (NF-κB), la vía de la quinasa c-Jun N-terminal (JNK), las vías del inflamasoma y autofagia provocando la destrucción tisular y creación de un estado proinflamatorio en la periodontitis.


Abstract During periodontitis inflammatory mediators and reactive oxygen species (ROS) are released, when they increase they produce oxidative stress. This review article describes the role played by ROS and oxidative stress in the development and evolution of inflammation and tissue injury during periodontitis. For this, a review of the literature was carried out in databases such as PubMed, ScienceDirect, Wiley Online Library, Springer, Plos one, Nature, Sage journals, Hindawi and Taylor & Francis Online, showing the following results: ROS produce direct damage and indirect to periodontal tissues. Direct damages include lipid peroxidation, protein and DNA oxidation. Indirect damage involves the regulation of signaling pathways of the nuclear transcription factor kappa B (NF-κB), the c-Jun N-terminal kinase pathway (JNK), the pathways of inflammasome and autophagy causing tis- sue destruction and creation of a pro-inflammatory state in periodontitis.


Resumo Durante a periodontite, são liberados mediadores inflamatórios e espécies reati- vas de oxigênio (EROs), no momento em que eles incrementam produzem estresse oxidativo. Este artigo de revisão descreve o papel que desempenham as EROS e o estresse oxidativo no desenvolvimento e na evolução da inflamação e lesão tecidual durante a periodontite. Por isso, uma revisão da literatura foi realizada em bancos de dados como PubMed, ScienceDirect, Wiley Online Library, Springer, Plos one, Nature, Sage, Hindawi e Taylor & Francis Online, mostrando os seguintes resultados: as EROS produzem dano direto e indireto para os tecidos periodontais. O dano direto inclui peroxidação lipídica, oxidação de proteínas e DNA. O dano indireto involucra a regulação das vias de sinalização do fator de transcrição nuclear kappa B (NF-κB), da via c-Jun N-terminal kinase (JNK), das vias inflamassoma e autofagia, causando destruição tecidual e criação de um estado pró-inflamatório na periodontite.

15.
Rev. colomb. ciencias quim. farm ; 49(2): 401-431, May-Aug. 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1144359

RESUMO

SUMMARY Aims: This study investigated the bioactivity of the crude leaf extract (CLE) and fractions hexane (HX) and ethyl acetate (EtOAc) from Talinum paniculatum alone and in association with fluconazole (FLC) against reference strain and clinical isolates of FLC-resistant Candida albicans. Furthermore, the antioxidant capability, chemical composition of this plant, and the effect's underlying mechanisms were evaluated. Methods: The antifungal activity was evaluated using checkerboard assay to establish the minimum inhibitory (MIC) and minimum microbicidal concen trations (MMC). During FLC and plant products challenges, the reactive oxygen species (ROS) generation (hydroxyl radicals [HO●]) were detected in C. albicans cells using the membrane-permeable fluorescent probes APF and HPF. High-performance liquid chromatography (HPLC) profile, quantitative analysis of antioxidant compounds, and free radical scavenging activity (DPPH assay) tests were performed. Results: The CLE and fractions presented outstanding antifungal activity and selectivity against C. albicans cells but had no synergistic effect's with FLC. The MIC values for CLE and its fractions against C. albicans reference strain were in the order of HX (31.25 µg ml-1) < EtOAc (62.5 μg ml-1) < CLE (500 μg ml-1), and against FLC-resistant C. albicans HX (125 μg ml-1) = EtOAc < CLE (500 μg ml-1). CLE and its fractions had more potent antifungal activities than FLC against the clinical isolates. Moreover, fungicidal effect's for these plant products were demonstrated against FLC-resistant C. albicans, which further conirmed an antifungal potential. Conversely, during association, plant products were shown to cause an increase in FLC MIC anywhere from 2- to 16-fold. FLC exposure led to an increase in the steady-state levels of ROS (HO●) in C. albicans cells. Next, we found that the increases in FLC MICs were owing to action of antioxidants containing-CLE and its fractions in preventing FLC-induced ROS-mediated growth inhibition of C. albicans. Conclusion: T. paniculatum can be a source of bioactive compounds with antifungal potential. However, because of the common use of its edible leaf, caution is advised during therapy with FLC (since it can decrease FLC susceptibility).


RESUMEN Objetivos: este estudio investigó la bioactividad del extracto de hoja en bruto (EHB) y las fracciones hexano (HX) y acetato de etilo (AcOEt) de Talinum paniculatum solo y en asociación con fluconazol (FLC) contra cepas de referencia y aislados clínicos de Candida albicans resistente a FLC. Además, evaluó la capacidad antioxidante, la composición química de esta planta y los mecanismos subyacentes del efecto fungicida. Métodos: la actividad antifúngica se evaluó mediante microdilución en caldo para establecer las concentraciones inhibitorias mínimas (CIM) y microbicidas mínimas (CMM). Durante el tratamiento con FLC y productos vegetales se detectó la generación de especies reactivas de oxígeno (ERO) (radicales hidroxilo [HO●]) en células de C. albicans utilizando las sondas fluorescentes permeables a la membrana APF y HPF. El perfil de cromatografía líquida de alta resolución (CLAR), el análisis cuantitativo de compuestos antioxidantes y el ensayo DPPH fueron evaluados. Resultados: el EHB y las fracciones presentaron una excelente actividad antifúngica y selectividad contra las células de C. albicans, pero no tuvieron efectos sinérgicos con FLC. Los valores de CIM para EHB y sus fracciones contra la cepa referencia de C. albicans fueron del orden de: HX (31,25 μg ml-1) < AcOEt (62,5 μg ml-1) < EHB (500 μg ml-1), y contra C. albicans resistente a FLC: HX (125 μg ml-1)= AcOEt < EHB (500 µg ml-1). EHB y sus fracciones fueron más potentes antifúngicos que FLC contra los aislados clínicos. Además, estos productos vegetales tienen efectos fungicidas contra C. albicans resistentes a FLC, esto conirmó el potencial antifúngico. Por el contrario, durante la asociación se demostró que los productos vegetales causan un aumento en la CIM de FLC de 2 a 16 veces. La exposición a FLC aumentó los niveles de ERO (HO●) en las células de C. albicans. Los aumentos en las CIM de FLC se debieron a la acción de los antioxidantes presentes en EHB y sus fracciones para prevenir la inhibición del crecimiento mediada por ERO inducida por FLC en C. albicans. Conclusión: T. paniculatum puede ser una fuente de compuestos bioactivos con potencial antifúngico. Sin embargo, debido al uso común de su hoja comestible, se recomienda usarla con precaución durante la terapia con FLC (ya que puede disminuir la susceptibilidad a FLC).

16.
Rev. chil. obstet. ginecol. (En línea) ; 84(5): 372-378, oct. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1058163

RESUMO

RESUMEN Introducción y objetivos: La endometriosis es una de las principales patologías ginecológicas que afecta a mujeres en edad reproductiva. Existen muchas teorías en cuanto a su fisiopatología destacando las alteraciones genéticas y epigenéticas, los desbalances hormonales y otros factores como la inflamación crónica y el estrés oxidativo; pero en realidad, su origen continúa siendo desconocido. Estudios recientes han implicado al estrés oxidativo y la consecuente generación de radicales libres de oxígeno en la fisiopatología de la entidad mediante la generación de inflamación crónica pélvica. El objetivo de este estudio es corroborar que existen vías de estrés oxidativo que se encuentran alteradas en estas pacientes. Métodos: Se realizará un análisis de marcadores de estrés oxidativo en plasma sanguíneo, entre ellos los niveles de proteínas carboniladas y el cociente glutatión oxidado/glutatión reducido (GSSG/GSH), comparando los resultados en pacientes con endometriosis (n=19) versus un grupo control (n=11). Resultados: existe un incremento de las proteínas carboniladas en las pacientes con endometriosis (p < 0,041). No se obtuvieron diferencias estadísticamente significativas en relación al cociente GSSG/GSH o a los niveles de GSH. Conclusión: existe evidencia para relacionar al estrés oxidativo con la fisiopatología de la endometriosis, sin poder determinar a día de hoy que vías de oxidación están implicadas.


ABSTRACT Introduction and objectives: Endometriosis is one of the main gynecological pathologies that affects women of reproductive age. There are many theories regarding its physiopathology highlighting genetic and epigenetic alterations, hormonal imbalances and other factors such as chronic inflammation and oxidative stress; but actually, its origin continues to be unknown. Recent studies have implicated oxidative stress and the consequent generation of oxygen free radicals in the physiopathology of the entity through the generation of chronic pelvic inflammation. The objective of this study is to corroborate that there are oxidative stress pathways that are altered in these patients. Methods: An analysis of oxidative stress biomarkers in blood plasma will be carried out, including carbonylated protein levels and the oxidized/reduced glutathione ratio (GSSG / GSH), comparing the results in patients with endometriosis (n = 19) versus a control group (n = 11). Results: there is an increase of carbonylated proteins in patients with endometriosis (p <0.041). There were no statistically significant differences in relation to the GSSG/GSH ratio or GSH levels. Conclusion: there is evidence to relate oxidative stress to the pathophysiology of endometriosis, without being able to determine to date which oxidation pathways are involved.


Assuntos
Humanos , Feminino , Estresse Oxidativo , Endometriose/diagnóstico , Espécies Reativas de Oxigênio , Endometriose/patologia , Glutationa , Antioxidantes
17.
Rev. peru. biol. (Impr.) ; 26(3)ago. 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1508843

RESUMO

Las algas pardas constituyen una fuente de alto contenido de polisacáridos como los fucoidanos que poseen importantes propiedades inmunomoduladoras. El objetivo fue determinar la viabilidad de células mononucleares de sangre periférica humana (CMSPh), producción de óxido nítrico (NO), especies reactivas de oxígeno (ROS) y de las citoquinas proinflamatorias IL-1α, IL-6, TNF-α e IFN-γ en cultivos tratados con fucoidan de Lessonia trabeculata. Se empleó fucoidan de Lessonia trabeculata proveniente de la bahía San Nicolás de Marcona-Ica. Las CMSPh se aislaron empleando Ficoll-Hypaque, se distribuyeron a una concentración de 1x105 células/pocillo en medio RPMI-1640 completo y se trataron con diferentes concentraciones de fucoidan durante 24 y 48 h. La actividad citotóxica se determinó por la reducción de MTT, la producción de NO por la reacción de Griess y las ROS por la reducción del NBT. La producción de citoquinas se cuantificó por ELISA. El fucoidan de L. trabeculata estimuló la proliferación de CMSPh y produjo el incremento de ROS a concentraciones de 100-2000 μg/mL respecto al control (p<0.001), la reacción para nitritos resultó negativa. El fucoidan incrementó la producción de IL-1α y TNF-α a concentraciones de 100 y 10 μg/mL respectivamente, mientras que la producción de IL-6 e IFN-γ no mostró diferencias significativas. Se concluye que el fucoidan de L. trabeculata estimula la proliferación de CMSPh, producción de especies reactivas de oxígeno y las citoquinas proinflamatorias IL-1α y TNF-α que poseen importantes propiedades inmunomoduladoras.


Brown algae are a source of high content of polysaccharides such as fucoidans that have important immunomodulatory properties. The aim was to determine the viability of human peripheral blood mononuclear cells (hPBMC), production of nitric oxide (NO), reactive oxygen species (ROS) and the proinflammatory cytokines IL-1α, IL-6, TNF-α and IFN -γ in cultures treated with fucoidan from Lessonia trabeculata. Fucoidan from Lessonia trabeculata from San Nicolás de Marcona-Ica Bay was used. The hPBMC were isolated using Ficoll-Hypaque, distributed at a concentration of 1x105 cells/well in complete RPMI-1640 medium and treated with different concentrations of fucoidan for 24 and 48 h. The cytotoxic activity was determined by the reduction of MTT, NO production by the Griess reaction and ROS by the reduction of NBT. The production of cytokines was quantified by ELISA. The fucoidan of L. trabeculata stimulated the proliferation of hPBMC and produced the increase of ROS at concentrations of 100-2000 μg/mL with respect to the control (p <0.001), the reaction for nitrites was negative. Fucoidan increased the production of IL-1α and TNF-α at concentrations of 100 and 10 μg/mL respectively, while the production of IL-6 and IFN-γ did not show significant differences. It is concluded that the fucoidan of L. trabeculata stimulates the proliferation of hPBMC, production of reactive oxygen species and the proinflammatory cytokines IL-1α and TNF-α that possess important immunomodulatory properties.

18.
Neurologia (Engl Ed) ; 2019 Mar 08.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30857788

RESUMO

INTRODUCTION: Overpopulation and industrial growth result in an increase in air pollution, mainly due to suspended particulate matter and the formation of ozone. Repeated exposure to low doses of ozone, such as on a day with high air pollution levels, results in a state of chronic oxidative stress, causing the loss of dendritic spines, alterations in cerebral plasticity and in learning and memory mechanisms, and neuronal death and a loss of brain repair capacity. This has a direct impact on human health, increasing the incidence of chronic and degenerative diseases. DEVELOPMENT: We performed a search of the PubMed, Scopus, and Google Scholar databases for original articles and reviews published between 2000 and 2018 and addressing the main consequences of ozone exposure on synaptic plasticity, information processing in cognitive processes, and the alterations that may lead to the development of neurodegenerative diseases. CONCLUSIONS: This review describes one of the pathophysiological mechanisms of the effect of repeated exposure to low doses of ozone, which causes loss of synaptic plasticity by producing a state of chronic oxidative stress. This brain function is key to both information processing and the generation of structural changes in neuronal populations. We also address the effect of chronic ozone exposure on brain tissue and the close relationship between ozone pollution and the appearance and progression of neurodegenerative diseases.

19.
Rev. biol. trop ; 66(4): 1469-1480, oct.-dic. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1003338

RESUMO

Abstract Gall-inducing insects manipulate the structural, histochemical and physiological profiles of host-plant tissues to develop galls. We evaluated galls induced by Eugeniamyia dispar on the leaves of Eugenia uniflora in an attempt to answer the following questions: (i) How does this gall-inducing insect change the structural and histochemical profiles of the host-plant organ? (ii) Despite structural changes, can gall tissues maintain photosynthetic activity? Starch, proteins, reducing sugars and reactive oxygen species were detected mainly in the nutritive tissue surrounding the larval chamber. Despite structural changes, the galls induced by E. dispar on E. uniflora retain chlorophyllous tissue, although its amount and photosynthetic activity are less than that of non-galled leaves. This reduced photosynthetic activity, in association with the presence of large intercellular spaces, could improve gas diffusion and, consequently, avoid hypoxia and hypercarbia in gall tissue.(AU)


Resumen Los insectos que inducen las agallas manipulan los perfiles estructurales, histoquímicos y fisiológicos de los tejidos de la planta hospedera para su desarrollo. Nosotros evaluamos las agallas inducidas por Eugeniamyia dispar en las hojas de Eugenia uniflora en un intento de responder las siguientes preguntas: (i) ¿Cómo este insecto inductor de agallas cambia los perfiles estructurales e histoquímicos en el órgano de la planta hospedera? (ii) A pesar de las modificaciones estructurales, ¿pueden los tejidos de la agalla mantener la actividad fotosintética? El almidón, las proteínas, los azúcares reductores y las especies reactivas de oxígeno se detectaron principalmente en la capa de tejido nutritivo que rodea a la cavidad larval. A pesar de las modificaciones estructurales, las agallas inducidas por E. dispar en E. uniflora retienen su tejido clorofílico, aunque su cantidad y actividad fotosintética son menores que en las hojas no agalladas. Esta actividad fotosintética reducida, asociado a la presencia de grandes espacios intercelulares, pueden mejorar la difusión de gases y, en consecuencia, evitar la hipoxia y la hipercapnia en los tejidos de las agallas.(AU)


Assuntos
Fotossíntese , Dípteros , Eugenia , Clorofila A , Hipóxia
20.
Int. j. morphol ; 36(4): 1310-1315, Dec. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-975701

RESUMO

Exposure to normobaric hyperoxia (NH) is known to increase the production of reactive oxygen species (ROS) by mitochondria. The present study was designed to examine mitochondrial ultrastructure morphological changes in the cortical brainin relation to glutathione peroxidase (GPX) activity and free radicals (FR) productions in brain tissue during hyperoxia exposure. The experimental groups were exposed to NH for 24 and 48 h continuously. Following the exposure periods, animals were sacrificed and cortical tissues were divided randomly into two parts; the first part was processed for the ultrastructural examination and the second was homogenized for GPX and FR determinations. Analysis of variance (ANOVA) showed that the main effects of O2 exposure periods were significant (p<0.05) for GPX and FR. Pair-wise means comparisons showed that NH elevated the average (+SE) GPX activity significantly (p<0.05) from the baseline control value of 5670.99+556.34 to13748.42+283.04 and 15134.19+1529.26 U/L with increasing length of NH exposure period from 24 to 48 h, respectively. Similarly, FR production was increased significantly (p<0.05) to 169.73+10.31 and 185.33+21.87, above baseline control of 105.27+5.25 Unit. Ultrastructure examination showed that O2 breathing for 48 h resulted in giant and swelled mitochondria associated with diluted inner membrane and damaged cristae. These mitochondria pathological alterations were associated with damages of myelin, axonal and cellular organelles. Normobaric-hyperoxia inducts mitochondria oxidative stress (MOS) and the subsequent rise of ROS causes variety of ultrastructure morphological pathological alterations in the organelles of cortical brain cells.


Se sabe que la exposición a la hiperoxia normobárica (HN) aumenta la producción de especies reactivas de oxígeno (ERO) por parte de las mitocondrias. El estudio se diseñó para examinar los cambios morfológicos de la ultraestructura mitocondrial en la corteza cerebral con la actividad de la glutatión peroxidasa (GPX) y la producción de radicales libres (RL) en el tejido cerebral durante la exposición a la hiperoxia. Los grupos experimentales fueron expuestos a HN durante 24 y 48 h continuamente. Tras los períodos de exposición, los animales se sacrificaron y los tejidos corticales se dividieron aleatoriamente en dos partes; la primera parte se procesó para el examen ultraestructural y la segunda se homogeneizó para las determinaciones de GPX y RL. El análisis de varianza (ANOVA) mostró que los efectos principales de los períodos de exposición al O2 fueron significativos (p <0,05) para GPX y RL. Las comparaciones de medias por pares mostraron que la HN elevó la actividad promedio de GPX (+ SE) significativamente (p <0,05) desde el valor de control de línea base de 5670,99 + 556,34 a 13748,42 + 283,04 y 15134,19 + 1529,26 U / L con una mayor duración del período de exposición a HN de 24 a 48 h, respectivamente. De manera similar, la producción de RL se incrementó significativamente (p <0,05) a 169,73 + 10,31 y 185,33 + 21,87, por encima del control de referencia de 105,27 + 5,25 unidades. El examen de la ultraestructura mostró que la respiración de O2 durante 48 h dio lugar a mitocondrias gigantes e hinchadas asociadas con la membrana interna diluida y las crestas dañadas. Estas alteraciones patológicas de las mitocondrias se asociaron con daños de mielina, axones y organelos celulares. La hiperoxia normobárica induce el estrés oxidativo mitocondrial (MOS) y el posterior aumento de las ERO provoca una variedad de alteraciones patológicas y morfológicas en los organelos de las células cerebrales corticales.


Assuntos
Animais , Ratos , Córtex Cerebral/ultraestrutura , Hiperóxia/patologia , Mitocôndrias/patologia , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Análise de Variância , Espécies Reativas de Oxigênio , Ratos Wistar , Espécies Reativas de Nitrogênio , Glutationa Peroxidase/metabolismo , Mitocôndrias/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...