Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 533
Filtrar
1.
Physiol Behav ; 251: 113817, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35443198

RESUMO

AIMS: Oxidative stress and neuronal death are the primary reasons for the progression of amyloid-beta (Aß) deposition and cognitive deficits in Alzheimer's disease (AD). Ecdysterone (ecdy), a common derivative of ecdysteroids, possesses free radical scavenging and cognitive-improving effects. High-intensity interval training (HIIT) can be a therapeutic strategy for improving cognitive decline and oxidative stress. The present study was aimed to evaluate the effect of HIIT exercise and ecdy consumption synergistically on the changes in learning and memory functions, activities of hippocampal antioxidant enzymes, and neuronal population after AD induced by Aß in male rats. MATERIALS AND METHODS: Following ten days of Aß injection, HIIT exercise and ecdy treatment (10 mg/kg/day; P.O.) were initiated and continued for eight consecutive weeks in rats. At the end of the treatment period, the rat's learning and memory functions were assessed using Morris water maze and passive avoidance tests. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GRx), and changes in neuronal population were evaluated in rats' brains. RESULTS: The results indicated that Aß injection disrupted spatial/passive avoidance learning and memory in both tests, accompanied by a decrease in the SOD and CAT (as endogenous antioxidants) in rats' hippocampus. Additionally, Aß injection resulted in neuronal loss in the cerebral cortex and hippocampus. Although the consumption of ecdy separately improved spatial/passive avoidance learning and memory impairments, recovered hippocampal activity of SOD, CAT, GRx, and prevented the hippocampal neuronal loss, its combination along with HIIT resulted in a more powerful and effective amelioration in all the above-mentioned Aß-neuropathological changes. CONCLUSION: Our results confirm that a combination of HIIT and ecdy treatment could be a promising potential therapeutic option against AD-associated cognitive decline, owing to their free radical scavenging and neuroprotective properties.


Assuntos
Doença de Alzheimer , Treinamento Intervalado de Alta Intensidade , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/metabolismo , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Aprendizagem da Esquiva , Modelos Animais de Doenças , Ecdisterona/farmacologia , Ecdisterona/uso terapêutico , Radicais Livres/efeitos adversos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto , Fragmentos de Peptídeos/farmacologia , Ratos , Superóxido Dismutase/metabolismo
2.
Free Radic Res ; 55(7): 745-756, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34085882

RESUMO

It has been shown that the development of coronavirus infection (COVID-19), especially in severe cases, is accompanied by hypoxia as a result of several pathological processes: alveolar blood supply disorders, hemolysis, COVID-associated coagulopathy. Under these conditions, the level of reactive oxygen species is increased and it is more likely that free-radical damage to biomolecules is caused by the process of free-radical fragmentation than oxidation. In contrast to the oxidation process, free-radical fragmentation reactions are more effectively inhibited by oxidizing agents than reducing agents. Therefore, the use of substances possessing both reducing and oxidizing properties, such as natural and synthetic quinones, bioflavonoids, curcuminoids, should reduce the probability of biomolecule destruction by oxidation as well as free-radical fragmentation processes.HighlightsCOVID-19 is accompanied by the iron release from the heme and «silent¼ hypoxiaROS initiate fragmentation reactions of biomolecules under conditions of hypoxiaBlocking of fragmentation process by oxidizers may lead to mitigation of COVID-19.


Assuntos
COVID-19/metabolismo , Radicais Livres/metabolismo , SARS-CoV-2/metabolismo , COVID-19/patologia , COVID-19/virologia , Radicais Livres/efeitos adversos , Heme/metabolismo , Humanos , Ferro/metabolismo , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , SARS-CoV-2/patogenicidade
3.
Int J Mol Sci ; 22(5)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33670966

RESUMO

3-hydroxytyrosol (HT) is the main phenolic compound found in olive oil with known antioxidant, anti-inflammatory, and antimicrobial properties in several dermatological conditions, both when taken in the form of olive oil or pure in cosmeceutical formulations. To date, its direct effect on the wound healing process and the molecular mechanisms involved have not yet been elucidated. Thus, in the present study, we aimed to explore its effects in vitro in epidermal keratinocyte cultures focusing on the molecular mechanism implied. HT was able to induce keratinocyte proliferation in the low micromolar range, increasing the expression of cyclin dependent kinases fundamental for cell cycle progression such as CDK2 and CDK6. Furthermore, it increased cell migration through the activation of tissue remodeling factors such as matrix metalloproteinase-9 (MMP-9) protein. Then, we evaluated whether HT also showed antioxidant activity at this concentration range, protecting from H2O2-induced cytotoxicity. The HT prevented the activation of ATM serine/threonine kinase (ATM), Checkpoint kinase 1 (Chk1), Checkpoint kinase 2 (Chk2), and p53, reducing the number of apoptotic cells. Our study highlighted novel pharmacological properties of HT, providing the first evidence of its capability to induce keratinocyte migration and proliferation required for healing processes and re-epithelialization.


Assuntos
Movimento Celular , Proliferação de Células , Epiderme/fisiologia , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/efeitos adversos , Queratinócitos/fisiologia , Álcool Feniletílico/análogos & derivados , Antioxidantes/farmacologia , Células Cultivadas , Epiderme/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/efeitos adversos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Oxidantes/efeitos adversos , Álcool Feniletílico/farmacologia , Transdução de Sinais , Cicatrização
4.
Chem Res Toxicol ; 33(10): 2527-2537, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-32909746

RESUMO

Electronic cigarettes (ECs) are categorized into generations which differ in terms of design, aerosol production, and customizability. Current and former smokers prefer third-generation devices that satisfy tobacco cravings more effectively than older generations. Recent studies indicate that EC aerosols from first- and second-generation devices contain reactive carbonyls and free radicals and can cause in vitro cytotoxicity. Third-generation ECs have not been adequately studied. Further, previous studies have focused on cells from the respiratory tract, whereas those of the oral cavity, which is exposed to high levels of EC aerosols, have been understudied. We quantified the production of reactive carbonyls and free radicals by a third-generation EC and investigated the induction of cytotoxicity and oxidative stress in normal and cancerous human oral cell lines using a panel of eight commercial EC liquids. We found that EC aerosols produced using a new atomizer contained formaldehyde, acetaldehyde, and acrolein, but did not contain detectable levels of free radicals. We found that EC aerosols generated from only one of the eight liquids tested using a new atomizer induced cytotoxicity against two human oral cells in vitro. Treatment of oral cells with the cytotoxic EC aerosol caused a concomitant increase in intracellular oxidative stress. As atomizer age increased with repeated use of the same atomizer, carbonyl production, radical emissions, and cytotoxicity increased. Overall, our results suggest that third-generation ECs may cause adverse effects in the oral cavity and normal EC use, which involves repeated use of the same atomizer to generate aerosol, may enhance the potential toxic effects of third-generation ECs.


Assuntos
Aerossóis/efeitos adversos , Sistemas Eletrônicos de Liberação de Nicotina , Sobrevivência Celular/efeitos dos fármacos , Radicais Livres/efeitos adversos , Humanos , Células Tumorais Cultivadas
5.
Int J Med Mushrooms ; 22(2): 183-195, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479006

RESUMO

The objective of this study was to explore the effect of magnesium acetate (MA) addition on the endo-polyphenol yield by Phellinus baumii and establish a feasible additive strategy. The optimal three-point MA addition strategy (0.05 g/L concentration of MA added at 0 h and 6 h, 0.9 g/L concentration of MA added at 12 h) was employed to obtain maximum endo-polyphenol yield. The maximum endo-polyphenol production was reached at 1.22 g/L, which was 1.39-fold higher than that of the control. Additionally, the endo-polyphenol showed stronger antioxidant activity in vitro compared with the control, including DPPH· scavenging capacity (78.76%) and Trolox equivalent antioxidant capacity (TEAC) (32.28 µmol Trolox/g sample). HPLC analysis showed that the endo-polyphenol production of the crude ethanol extracts was significantly higher than that of the control. Hispidin was isolated and identified from the ethanol extract of the culture mycelia from Ph. baumii with the three-point MA addition strategy. Hispidin showed a strong ability to scavenge DPPH free radicals and TEAC, equivalent to positive (vitamin C) value of 89.41% and 75.98%, respectively. Furthermore, hispidin protected H2O2-induced PC12 cells injured by decreased oxidative stress level. These results indicated that the MA multi-stage addition strategy was dependable, and could be used to develop new natural antioxidants for foods or medicines.


Assuntos
Acetatos/efeitos adversos , Antioxidantes/farmacologia , Basidiomycota/química , Misturas Complexas/farmacologia , Compostos de Magnésio/efeitos adversos , Polifenóis/farmacologia , Pironas/farmacologia , Agaricales , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Cromanos/efeitos adversos , Cromatografia Líquida de Alta Pressão , Misturas Complexas/química , Misturas Complexas/isolamento & purificação , Radicais Livres/efeitos adversos , Peróxido de Hidrogênio/efeitos adversos , Micélio/química , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Polifenóis/química , Polifenóis/isolamento & purificação , Pironas/química , Pironas/isolamento & purificação , Ratos
6.
Infect Disord Drug Targets ; 20(1): 16-26, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-29952268

RESUMO

Free radicals are generated in our body by several systems. A balance among free radicals and antioxidants is an important matter for appropriate physiological function. If free radicals become greater than the ability of the body to control them, a case known as oxidative stress appears, as a result of that, a number of human diseases spread in the body. Antioxidants can contribute to facingthis oxidative stress. The present review provides a brief overview of free radicals, oxidative stress, some natural antioxidants and the relationship between them.


Assuntos
Antioxidantes/farmacologia , Radicais Livres/efeitos adversos , Antioxidantes/uso terapêutico , Humanos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
7.
Adv Exp Med Biol ; 1155: 483-495, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468425

RESUMO

The loss of pancreatic ß-cells plays a central role in the pathogenesis of both type 1 and type 2 diabetes, and many studies have been focused on ways to improve glucose homeostasis by preserving, expanding and improving the function of ß-cell. Elevated levels of free fatty acids such as palmitate might contribute to the loss of ß-cells. A marine squid, Loliolus beka has long been used as a food in Korea, China, Japan and Europe due to its tender meat and high taurine content. Here, we investigated the protective effects of a hot water extract of Loliolus beka meat (LBM) against palmitate toxicity in Ins-1 cells, a rat ß-cell line. Treatment with LBM extract protected against palmitate-induced cytotoxicity and scavenged overproduction of nitric oxide, alkyl, and hydroxyl radicals. In addition, LBM extract protected against palmitate-induced DNA damage and ß-cell dysfunction. These findings suggest that LBM protects pancreatic ß-cells from palmitate-induced damage. LBM could be a potential therapeutic functional food for diabetes.


Assuntos
Extratos Celulares/farmacologia , Dano ao DNA , Decapodiformes/química , Radicais Livres/efeitos adversos , Células Secretoras de Insulina/efeitos dos fármacos , Palmitatos/efeitos adversos , Taurina/farmacologia , Animais , Apoptose , Linhagem Celular , Diabetes Mellitus , Carne , Ratos
9.
Adv Anat Embryol Cell Biol ; 231: 105-126, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30610376

RESUMO

Tucked inside our cells, we animals (and plants, and fungi) carry mitochondria, minuscule descendants of bacteria that invaded our common ancestor 2 billion years ago. This unplanned breakthrough endowed our ancestors with a convenient, portable source of energy, enabling them to progress towards more ambitious forms of life. Mitochondria still manufacture most of our energy; we have evolved to invest it to grow and produce offspring, and to last long enough to make it all happen. Yet because the continuous generation of energy is inevitably linked to that of toxic free radicals, mitochondria give us life and give us death. Stripping away clutter and minutiae, here we present a big-picture perspective of how mitochondria work, how they are passed on virtually only by mothers, and how they shape the lifestyles of species and individuals. We discuss why restricting food prolongs lifespan, why reproducing shortens it, and why moving about protects us from free radicals despite increasing their production. We show that our immune cells use special mitochondria to keep control over our gut microbes. And we lay out how the fabrication of energy and free radicals sets the internal clocks that command our everyday rhythms-waking, eating, sleeping. Mitochondria run the show.


Assuntos
Envelhecimento/metabolismo , Radicais Livres/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Envelhecimento/fisiologia , Animais , Antioxidantes/farmacologia , Restrição Calórica , Ritmo Circadiano/genética , Ritmo Circadiano/fisiologia , Radicais Livres/efeitos adversos , Microbioma Gastrointestinal/imunologia , Hereditariedade/genética , Humanos , Leucócitos/imunologia , Leucócitos/microbiologia , Estilo de Vida , Longevidade/genética , Longevidade/fisiologia , Mitocôndrias/química , Reprodução/genética , Reprodução/fisiologia
10.
Aging Cell ; 18(1): e12843, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30334314

RESUMO

The identification of conserved genes and pathways that regulate lifespan but also healthspan has resulted in an improved understanding of the link between nutrients, signal transduction proteins, and aging but has also provided evidence for the existence of multiple "longevity programs," which are selected based on the availability of nutrients. Periodic fasting and other dietary restrictions can promote entry into a long-lasting longevity program characterized by cellular protection and optimal function but can also activate regenerative processes that lead to rejuvenation, which are independent of the aging rate preceding the restricted period. Thus, a "juventology"-based strategy can complement the traditional gerontology approach by focusing not on aging but on the longevity program affecting the life history period in which mortality is very low and organisms remain youthful, healthy, and fully functional.


Assuntos
Restrição Calórica , Dieta com Restrição de Proteínas , Jejum/fisiologia , Expectativa de Vida , Longevidade/genética , Rejuvenescimento/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Radicais Livres/efeitos adversos , Hormônio do Crescimento/antagonistas & inibidores , Humanos , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Camundongos , Pessoa de Meia-Idade , Nutrientes/fisiologia , Proteínas Quinases S6 Ribossômicas/antagonistas & inibidores , Saccharomyces cerevisiae/metabolismo , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Adulto Jovem
11.
Rev. Rol enferm ; 41(11/12): 739-744, nov.-dic. 2018. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-179765

RESUMO

El exceso de radicales libres en el entorno de una herida contribuye de forma significativa al estancamiento de la misma en la fase inflamatoria, favoreciendo la aparición de una herida de difícil cicatrización. Se genera una situación de estrés oxidativo, puesto que las enfermedades de base que suelen presentar los pacientes con heridas crónicas dificultan en gran medida el retorno a una situación de balance oxidativo. Esto incide directamente sobre la capacidad de respuesta del tejido, ya que se afectan directamente estructuras celulares y la matriz extracelular del entorno. En este trabajo se ha aplicado un tratamiento antioxidante para el control del exceso de radicales libres en el entorno de la herida, con el fin de conseguir la activación en el caso de úlceras crónicas de etiología vascular venosa. Para ello, se ha aplicado un apósito antioxidante con componentes de origen natural, una matriz absorbente de algarrobo y una solución antioxidante con cúrcuma y acetilcisteína, indicado para la fase inflamatoria de las heridas y la adecuada terapia compresiva. Para la evaluación de la evolución de las úlceras se utilizó la escala RESVECH 2.0. Transcurridas 2-3 semanas, el apósito antioxidante consiguió la activación de la herida, lo que se reflejó en el mantenimiento del lecho de la úlceras libre de tejido desvitalizado, la inducción de la formación de tejido de granulación y la activación de los bordes perilesionales. A partir de ese momento, se aplicaron apósitos de cura húmeda convencionales, llegando hasta la cicatrización total de las heridas en las semanas 5-6 desde el inicio del tratamiento


The excess of free radicals in the wound environment significantly contributes to the arrest of the wound in the inflammatory phase, favoring the appearance of a hard-to-heal wound. An oxidative stress condition is generated, as the comorbidities that patients with chronic wounds frequently present hinder the return to an oxidative balance. This fact affects the ability of the tissue to respond to an injury, since cellular structures and extracellular matrix of the environment are affected. In this work, an antioxidant treatment has been applied, to control the excess of free radicals in the wound environment, in order to achieve the activation of chronic ulcers from venous vascular etiology. This antioxidant dressing has two components from natural origin, an absorbent matrix from carob tree and an antioxidant solution containing curcumin and acetylcysteine, and is indicated for the inflammatory phase of the healing process of wounds. The appropriate compressive therapy was also applied. RESVECH 2.0 scale was used as wound evolution assessment. The results showed that after 2-3 weeks of treatment, the antioxidant dressing achieved the activation of the wound, which was reflected in the maintenance of a wound bed free from devitalized tissue, the induction of the formation of granulation tissue and the activation of the perilesional edges. After that, conventional moist wound healing dressings were applied, reaching wound closure after 5-6 weeks from the beginning of the treatment


Assuntos
Humanos , Masculino , Feminino , Adulto , Idoso , Idoso de 80 Anos ou mais , Estresse Oxidativo/fisiologia , Cicatrização/fisiologia , Úlcera Varicosa/terapia , Antioxidantes/administração & dosagem , Sequestradores de Radicais Livres/administração & dosagem , Úlcera Varicosa/enfermagem , Bandagens , Radicais Livres/efeitos adversos , Curcuma , Acetilcisteína/uso terapêutico , Comorbidade
12.
Oxid Med Cell Longev ; 2018: 7483062, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30140369

RESUMO

During the perinatal period, free radicals (FRs) are involved in several physiological roles such as the cellular responses to noxia, the defense against infectious agents, the regulation of cellular signaling function, and the induction of a mitogenic response. However, the overproduction of FRs and the insufficiency of an antioxidant mechanism result in oxidative stress (OS) which represents a deleterious process and an important mediator of damage to the placenta and the developing fetus. After birth, OS can be magnified by other predisposing conditions such as hypoxia, hyperoxia, ischemia, hypoxia ischemia-reperfusion, inflammation, and high levels of nonprotein-bound iron. Newborns are particularly susceptible to OS and oxidative damage due to the increased generation of FRs and the lack of adequate antioxidant protection. This impairment of the oxidative balance has been thought to be the common factor of the so-called "free radical related diseases of prematurity," including retinopathy of prematurity, bronchopulmonary dysplasia, intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, kidney damage, and oxidative hemolysis. In this review, we provide an update focused on the factors influencing these diseases refining the knowledge about the role of OS in their pathogenesis and the current evidences of such relationship. Mechanisms governing FR formation and subsequent OS may represent targets for counteracting tissue damage.


Assuntos
Radicais Livres/efeitos adversos , Doenças do Prematuro/etiologia , Humanos , Doenças do Prematuro/patologia , Estresse Oxidativo
13.
Arab J Gastroenterol ; 19(2): 56-64, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29853428

RESUMO

Oxidative stress plays an important role in the pathogenesis of various chronic liver diseases (CLD) and increasing evidence have confirmed the contributory role of oxidative stress in the pathogenesis of drugs and chemical-induced CLD. Chronic liver injury is manifested as necrosis, cholestasis, fibrosis, and cirrhosis. Chronic administration of anti-tubercular, anti-retroviral, immunosuppressive drugs is reported to induce free radical generation during their biotransformation in the liver. Further, these reactive intermediates are said to induce profibrogenic cytokines, several inflammatory markers, collagen synthesis during the progression of hepatic fibrosis. Oxidative stress and free radicals are reported to induce activation and proliferation of hepatic stellate cells in the injured liver leading to the progression of CLD. Hence, to counteract or to scavenge these reactive intermediates, several plant-derived antioxidant principles have been effectively employed against oxidative stress and came out with promising results in human and experimental models of CLD. This review summarizes the relationships between oxidative stress and different liver pathogenesis induced by drugs and xenobiotics, focusing upon different chronic liver injury induced by alcohol, antitubercular drugs and hyperactivity of antiretroviral drugs in HIV patients, viral hepatitis infection induced oxidative stress.


Assuntos
Antioxidantes/fisiologia , Hepatopatias/etiologia , Hepatopatias/fisiopatologia , Estresse Oxidativo , Animais , Carcinoma Hepatocelular/fisiopatologia , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Doença Crônica , Radicais Livres/efeitos adversos , Hepatite/fisiopatologia , Humanos , Cirrose Hepática/fisiopatologia , Hepatopatias Alcoólicas/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , MicroRNAs/fisiologia , Estresse Oxidativo/genética
14.
Nihon Eiseigaku Zasshi ; 73(1): 51-56, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-29386447

RESUMO

Relatively high doses of psychostimulants induce neurotoxicity on the dopaminergic system and self-injurious behavior (SIB) in rodents. However the underlying neuronal mechanisms of SIB remains unclear. Dopamine receptor antagonists, N-methyl-D-aspartic acid (NMDA) receptor antagonists, Nitric Oxide Synthase (NOS) inhibitors and free radical scavengers significantly attenuate methamphetamine-induced SIB. These findings indicate that activation of dopamine as well as NMDA receptors followed by radical formation and oxidative stress, especially when mediated by NOS activation, is associated with methamphetamine-induced SIB. On the other hand, an increase in the incidence of polydrug abuse is a major problem worldwide. Coadministered methamphetamine and morphine induced lethality in more than 80% in mice, accompanied by an increase in the number of poly (ADP-ribose) polymerase (PARP)-immunoreactive cells in the heart, kidney and liver. The lethal effect and the increase in the incidence of rupture or PARP-immunoreactive cells induced by the coadministration of methamphetamine and morphine were significantly attenuated by pretreatment with a phospholipase A2 inhibitor or a radical scavenger, or by cooling of body from 30 to 90 min after drug administration. These results suggest that free radicals play an important role in the increased lethality induced by the coadministration of methamphetamine and morphine. Therefore, free radical scavengers and cooling are beneficial for preventing death that is induced by the coadministration of methamphetamine and morphine. These findings may help us better understand for masochistic behavior, which is a clinical phenomenon on SIB, as well as polydrug-abuse-induced acute toxicity.


Assuntos
Estimulantes do Sistema Nervoso Central/efeitos adversos , Estimulantes do Sistema Nervoso Central/toxicidade , Metanfetamina/efeitos adversos , Metanfetamina/toxicidade , Comportamento Autodestrutivo/induzido quimicamente , Animais , Antagonistas de Dopamina/farmacologia , Antagonistas de Dopamina/uso terapêutico , Neurônios Dopaminérgicos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/uso terapêutico , Radicais Livres/efeitos adversos , Radicais Livres/toxicidade , Humanos , Dose Letal Mediana , Metanfetamina/administração & dosagem , Morfina/administração & dosagem , Morfina/efeitos adversos , Morfina/toxicidade , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Comportamento Autodestrutivo/etiologia , Transtornos Relacionados ao Uso de Substâncias
15.
J Microbiol Biotechnol ; 28(4): 527-533, 2018 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-29385660

RESUMO

This study compared the radioprotective effects of high-molecular-weight poly-gamma-glutamate (γ-PGA, average molecular mass 3,000 kDa) and a reduced form of glutathione (GSH, a known radioprotector) on calf thymus DNA damage. The radiation-induced DNA damage was measured on the basis of the decreased fluorescence intensity after binding the DNA with ethidium bromide. All the experiments used 6°Co gamma radiation at 1,252 Gy, representing 50% DNA damage. When increasing the concentration of γ-PGA from 0.33 to 1.65 µM, the DNA protection from radiation-induced damage also increased, with a maximum of 87% protection. Meanwhile, the maximal DNA protection when increasing the concentration of GSH was only 70%. Therefore, γ-PGA exhibited significant radioprotective effects against gamma irradiation.


Assuntos
Cosmecêuticos/farmacologia , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Raios gama/efeitos adversos , Glutamatos/farmacologia , Protetores contra Radiação/farmacologia , Cosmecêuticos/administração & dosagem , Cosmecêuticos/química , DNA/efeitos dos fármacos , DNA/efeitos da radiação , Radicais Livres/efeitos adversos , Glutamatos/administração & dosagem , Glutamatos/química , Glutationa/metabolismo , Protetores contra Radiação/administração & dosagem , Protetores contra Radiação/química , Espectrometria de Fluorescência
16.
Artigo em Inglês | MEDLINE | ID: mdl-29341860

RESUMO

Frequent air travelers and airplane pilots may develop various types of illnesses. The environmental risk factors associated with air travel syndromes (ATS) or air travel-related adverse health outcomes raised concerns and need to be assessed in the context of risk management and public health. Accordingly, the aim of the present review was to determine ATS, risk factors, and mechanisms underlying ATS using scientific data and information obtained from Medline, Toxline, and regulatory agencies. Additional information was also extracted from websites of organizations, such as the International Air Transport Association (IATA), International Association for Medical Assistance to Travelers (IAMAT), and International Civil Aviation Organization (ICAO). Air travelers are known to be exposed to environmental risk factors, including circadian rhythm disruption, poor cabin air quality, mental stress, high altitude conditions, hormonal dysregulation, physical inactivity, fatigue, biological infections, and alcoholic beverage consumption. Consequences of ATS attributed to air travel include sleep disturbances (e.g., insomnia), mental/physical stress, gastrointestinal disorders, respiratory diseases, circulatory-related dysfunction, such as cardiac arrest and thrombosis and, at worst, mechanical and terrorism-related airplane crashes. Thus safety measures in the cabin before or after takeoff are undertaken to prevent illnesses or accidents related to flight. In addition, airport quarantine systems are strongly recommended to prepare for any ultimate adverse circumstances. Routine monitoring of environmental risk factors also needs to be considered. Frequently, the mechanisms underlying these adverse manifestations involve free radical generation. Therefore, antioxidant supplementation may help to reduce or prevent adverse outcomes by mitigating health risk factors associated with free radical generation.


Assuntos
Viagem Aérea , Antioxidantes/uso terapêutico , Radicais Livres/efeitos adversos , Medição de Risco , Estresse Fisiológico/fisiologia , Humanos , Fatores de Risco , Síndrome
17.
Curr Opin Pulm Med ; 24(2): 187-190, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29232278

RESUMO

PURPOSE OF REVIEW: Low-dose oxygen (LDO) supplementation is used by millions of COPD patients worldwide. The therapeutic benefits of LDO supplementation are well known. There are also several concerns regarding the potential for cellular harm from LDO in COPD patients. This review summarizes the current arguments and evidence pertaining to this important topic. RECENT FINDINGS: LDO therapy has been used in COPD patients for more than 50 years. Over the years, data from randomized controlled trials has confirmed that LDO provides survival benefit in COPD patients with severe hypoxemia. Recent data, however, show that LDO does not provide any morality benefit for patients with a less severe degree of hypoxemia. There are several theoretical concerns regarding use of LDO in COPD patients, including radiation-like cellular risks because of oxygen toxicity. However, none of these have been validated in human clinical trials and remain somewhat peripheral to the clinician deciding whether or not to initiate LDO in a hypoxemic COPD patient. SUMMARY: There is high-quality evidence that LDO is both well tolerated and highly efficacious for patients with COPD. There are several theoretical concerns regarding damage from oxygen free radicals from LDO in COPD patients. However, none of these have been validated or confirmed in human clinical trial data. Thus, the benefits of LDO clearly outweigh the risks from any theoretical concerns about oxygen toxicity.


Assuntos
Hipóxia/terapia , Oxigenoterapia , Oxigênio/administração & dosagem , Oxigênio/efeitos adversos , Doença Pulmonar Obstrutiva Crônica/terapia , Radicais Livres/efeitos adversos , Humanos , Hipóxia/etiologia , Oxigenoterapia/efeitos adversos , Oxigenoterapia/métodos , Doença Pulmonar Obstrutiva Crônica/complicações
18.
Nutr. hosp ; 34(4): 869-874, jul.-ago. 2017. tab, graf
Artigo em Inglês | IBECS | ID: ibc-165349

RESUMO

Introduction: The relationship between diet and health has aroused scientific interest, especially the consumption of antioxidant nutrients naturally present in foods, because of its action against the deleterious effects of free radicals in the body. Objective: This study aimed to estimate the intake of antioxidant nutrients and its relationship with lipid profile and oxidative stress in student users of a university restaurant in comparison with non-users. Methods: This cross-sectional study involved 145 university students divided into two groups: users of the university restaurant (group 1, n = 73) and non-users (group 2, n = 72). We measured body mass index and waist circumference, and estimated the intake of antioxidant micronutrients. Serum concentrations of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglyceride levels, and plasma concentrations of malondialdehyde were determined. Results and conclusion: Intake of copper, zinc, selenium, and vitamin C were within the recommendations in both groups, and vitamins A and E were below the reference values. There was a correlation between the intake of vitamin C and triglycerides. Group 1 members had better dietary patterns in relation to antioxidant micronutrients, reflecting less atherogenic lipid profile and lower exposure to oxidative stress compared to group 2 (AU)


Introducción: la relación entre la dieta y la salud ha despertado interés científico, especialmente en lo referente al consumo de nutrientes antioxidantes presentes de forma natural en los alimentos, debido a su acción contra los efectos nocivos de los radicales libres en el cuerpo. Objetivo: el objetivo de este estudio fue estimar la ingesta de nutrientes antioxidantes y su relación con el perfil lipídico y el estrés oxidativo en estudiantes usuarios de un restaurante universitario, en comparación con los no usuarios. Métodos: este es un estudio transversal que incluye 145 estudiantes universitarios, divididos en dos grupos: los usuarios del restaurante universitario (grupo 1, n = 73) y no usuarios (grupo 2, n = 72). Fueron medidos el índice de masa corporal y la circunferencia de la cintura, y se estimó la ingesta de micronutrientes antioxidantes. Se determinaron las concentraciones séricas de colesterol total, colesterol unido a lipoproteínas de alta densidad, colesterol unido a lipoproteínas de baja densidad, los niveles de triglicéridos y las concentraciones plasmáticas de malondialdehído. Resultados y conclusiones: la ingesta de cobre, zinc, selenio y la vitamina C se encontraba dentro de las recomendaciones de los dos grupos, y la de vitaminas A y E estaba por debajo de los valores de referencia. Hubo una correlación entre el consumo de vitamina C y los triglicéridos. Miembros del grupo 1 mostraron mejores patrones dietéticos en relación con micronutrientes antioxidantes, lo que refleja menos perfil lipídico aterogénico y una menor exposición al estrés oxidativo en comparación con el grupo 2 (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Nutrientes/métodos , Antioxidantes/administração & dosagem , Estresse Oxidativo/fisiologia , Micronutrientes/uso terapêutico , Índice de Massa Corporal , Ácido Ascórbico/uso terapêutico , Radicais Livres/efeitos adversos , Estudos Transversais/métodos , Relação Cintura-Quadril/métodos , Cobre/uso terapêutico , Zinco/uso terapêutico , Selênio/uso terapêutico , Vitamina A/uso terapêutico , Vitamina E/uso terapêutico
19.
Nutr. hosp ; 34(2): 469-478, mar.-abr. 2017. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-162511

RESUMO

Introducción: la influencia de los antioxidantes en los procesos oculares ha tomado en los últimos años una relevancia importante por sus efectos en la salud visual. El estrés oxidativo es un factor implicado en el desarrollo de las principales patologías tales como cataratas, glaucoma y degeneración macular asociada a la edad (DMAE). Objetivo: establecer la evidencia científica que existe sobre los distintos tipos de antioxidantes y sus efectos en procesos patológicos oculares mediante una revisión sistemática. Métodos: búsqueda bibliográfica en MEDLINE, Scielo y Cochrane de estudios que evalúan la utilización de antioxidantes en la prevención y/o tratamiento de las enfermedades oculares. Se seleccionaron ensayos clínicos controlados y aleatorizados publicados en los últimos 7 años. Resultados: la relación entre distintos tipos de antioxidantes, vitamina E, C, betacaroteno, zinc, luteína, antocianinas y carotenoides, sugiere una relación positiva ante el riesgo y progresión de DMAE y parámetros del glaucoma, indicando un menor riesgo de la enfermedad ante un mayor consumo de antioxidantes en la dieta. Informes iniciales sugieren un papel potencial para la modificación de la dieta en el tratamiento de la degeneración macular asociada a la edad y glaucoma principalmente, no evidenciándose para la prevención de la catarata. Conclusiones: promover el consumo adecuado de antioxidantes en la dieta puede prevenir y proteger frente a patologías oculares de gran prevalencia. Los antioxidantes del grupo de vitaminas son los más estudiados hasta el momento en las patologías oculares. Es necesario llevar a cabo más ensayos clínicos para establecer de forma más precisa estas relaciones (AU)


Introduction: The influence of antioxidants on ocular processes has taken on a significant importance in recent years for its effects on visual health. Oxidative stress is a factor involved in the development of major pathologies such as cataracts, glaucoma and age-related macular degeneration (AMD). Objective: To establish the scientific evidence that exists about the different types of antioxidants and their effects on ocular pathological processes through a systematic review. Methods: Literature search in MEDLINE, Scielo and Cochrane for studies evaluating the use of antioxidants in the prevention and/or treatment of eye diseases. Selected randomized controlled clinical trials over the past 7 years were selected. Results: The relationship between different types of antioxidants, vitamin E, C, beta carotene, zinc, lutein, anthocyanins and carotenoids, suggests a positive relationship with the risk and progression of AMD and glaucoma parameters, indicating a lower risk of the disease due to an increased consumption of antioxidants in the diet. Initial reports suggest a potential role for diet modification in the treatment of age-related macular degeneration and glaucoma primarily, not evidencing for the prevention of cataract. Conclusions: Promoting adequate consumption of antioxidants in the diet can prevent and protect against highly prevalent eye diseases. The antioxidants of the group of vitamins are the most studied so far in the ocular pathologies. More clinical trials are needed to establish these relationships more precisely (AU)


Assuntos
Humanos , Masculino , Feminino , Oftalmopatias/induzido quimicamente , Oftalmopatias/epidemiologia , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Carotenoides/efeitos adversos , Degeneração Macular/induzido quimicamente , Catarata/induzido quimicamente , Catarata/complicações , Vitamina E/administração & dosagem , Carotenoides/administração & dosagem , Ácido Ascórbico/efeitos adversos , Radicais Livres/administração & dosagem , Radicais Livres/efeitos adversos , Polifenóis/administração & dosagem , Polifenóis/efeitos adversos
20.
Respir Res ; 18(1): 15, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086957

RESUMO

BACKGROUND: Exposure to elevated levels of particulate matter (PM) is associated with increased risk of morbidity and mortality due to respiratory tract viral infections in infants. Recent identification of environmentally persistent free radicals (EPFRs) in the PM from a variety of combustion sources suggests its role in the enhancement of disease severity of lower respiratory tract infections (LRTI). Our previous studies demonstrated that acute exposure to EPFRs induces pulmonary immunosuppression allowing for enhanced influenza disease severity. Here, we determine the mechanism of EPFR-induced immunosuppression and its impact on the immune response towards influenza infection. METHODS: Neonatal mice (3 days old) were acutely exposed to DCB (combustion derived PM with chemisorbed EPFR) for seven consecutive days. Four days post-exposure (dpe), mice were infected with influenza virus. Pulmonary T cell phenotypes including regulatory T cells (Tregs) were analyzed by flow cytometry. The role of IL10 in EPFR-induced exacerbation of influenza disease severity was determined by administering recombinant IL10 (rIL10) to wild type mice or by using IL10 deficient (IL10-/-) neonatal mice. Mice were assessed for morbidity by measuring percent weight change and pulmonary viral load. RESULTS: Neonatal mice exposed to EPFRs had a significant increase in pulmonary Tregs and the immunosuppressive cytokine IL10 following influenza infection, which coincided with decreased protective T cell responses to influenza infection at 6 dpi. Depletion of Tregs in EPFR-exposed neonatal mice resulted in increased protective, adaptive T cell responses, whereas adoptive transfer of Tregs from EPFR-exposed neonates to air-exposed neonatal mice suppressed adaptive T cell responses towards influenza infection. Further, treatment with rIL10 could recapitulate EPFR-induced exacerbation of morbidity and pulmonary viral load compared to air exposed and influenza infected mice, whereas, EPFR-exposed IL10-/- neonates exhibited significant reductions in morbidity, pulmonary viral load and adaptive T cell responses following influenza infection. CONCLUSIONS: Neonatal exposure to EPFRs induced Tregs and IL10 resulting in suppressed adaptive T cell responses and enhanced influenza disease severity in neonatal mice. Depletion of Tregs increased adaptive T cell responses and deficiency of IL10 reduced morbidity and conferred enhanced protection against influenza virus.


Assuntos
Exposição Ambiental/efeitos adversos , Hospedeiro Imunocomprometido/imunologia , Influenza Humana/imunologia , Pulmão/imunologia , Material Particulado/efeitos adversos , Linfócitos T Reguladores/imunologia , Animais , Animais Recém-Nascidos , Citocinas/imunologia , Feminino , Radicais Livres/efeitos adversos , Humanos , Hospedeiro Imunocomprometido/efeitos dos fármacos , Influenza Humana/patologia , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...