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- ItemSomente Metadadadosalpha-Tocopherol supplementation avoids apoptosis in the anal sphincter(Informa Healthcare, 2012-03-01) Silva, Romualdo Correa da [UNIFESP]; Reis, Leonardo Oliveira; Lorenzetti, Fabio [UNIFESP]; Palma, Paulo; Ortiz, Valdemar [UNIFESP]; Dambros, Miriam [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)Purpose: To analyze the influence of alpha-tocopherol supplementation on the levels of oxidative stress and apoptosis rates in the anal sphincter induced by orchiectomy in rats. Methods: Forty male Wistar rats weighing 250-300 g, were divided into four groups and sacrificed 8 weeks after: I- Control: sham; II- Orchiectomy: bilateral orchiectomy; III- Pre Orchiectomy Tocopherol: alpha-tocopherol supplementation for 4 weeks preceding bilateral orchiectomy; IV- Orchiectomy Full Tocopherol: alpha-tocopherol supplementation for 4 weeks before and 8 weeks after bilateral orchiectomy. the anal sphincter was analyzed stereologically to evaluate the density of collagen and the muscle fibers. the oxidative stress and the apoptosis were determined with 8-isprostane and caspase-3, respectively. Results: the collagen fibers concentration was statistically greater in Orchiectomy group than the others. the muscle fibers concentration was higher in Control and Orchiectomy Full Tocopherol than Orchiectomy and Pre Orchiectomy Tocopherol groups. Orchiectomy group showed higher 8-isoprostane concentrations compared to the other groups (p < 0.0003). Pre Orchiectomy Tocopherol and Orchiectomy Full Tocopherol groups presented caspase-3 levels lower than the Orchiectomy group (0.0072). Conclusion: Vitamin supplementation with alpha-tocopherol for 12 weeks had the highest protection against bilateral orchiectomy generation of reactive oxygen species as well as apoptosis in the muscle fibers of the anal sphincter of rats.
- ItemSomente MetadadadosAscorbic acid and alpha-tocopherol attenuate methylmalonic acid-induced convulsions(Lippincott Williams & Wilkins, 1999-07-13) Fighera, M. R.; Queiroz, C. M.; Stracke, M. P.; Brauer, MCN; Gonzalez-Rodriguez, L. L.; Frussa, R.; Wajner, M.; Mello, C. F. de; Universidade Federal de Sergipe (UFS); Universidade Federal de São Paulo (UNIFESP); Univ Fed Rio Grande SulTHE effects of chronic administration of alpha-tocopherol or melatonin, or acute ascorbic acid administration on the convulsant action of methylmalonic acid (MMA) were investigated in adult male rats. Animals were chronically injected with alpha-tocopherol (40 mg kg(-1), i.p.), melatonin (5 mg kg(-1), i.p.) or vehicle for 7 days. Buffered MMA (6 mu mol/2 mu l) or NaCl (9 mu mol/2 mu l) was injected intrastriatally and the animals were observed for the appearance of clonic or tonic-clonic convulsions and rotational behavior. Ascorbic acid (100 mg kg(-1), s.c.) was administered 30 min before MMA injection. alpha-Tocopherol and ascorbic acid pretreatment decreased the duration of the convulsive episodes and the rotational behavior elicited by MMA, This study provides evidence that free radical generation may participate in the convulsant effects of methylmalonic acid. NeuroReport 10:2039-2043 (C) 1999 Lippincott Williams & Wilkins.
- ItemAcesso aberto (Open Access)Atividade antioxidante e alterações morfológicas induzidas pelas isoflavonas da soja no útero de ratas ovariectomizadas.(Universidade Federal de São Paulo (UNIFESP), 2014) Teixeira, Cristiane de Paula [UNIFESP]; Simões, Manuel de Jesus [UNIFESP]; http://lattes.cnpq.br/5987164343458678; http://lattes.cnpq.br/0572410240696130; Universidade Federal de São Paulo (UNIFESP)A diminuicao do estrogenio na pos-menopausa leva a perda de efeitos antioxidantes, promovendo o aumento de especies reativas de oxigenio e nitrogenio, favorecendo a ocorrencia de lesoes oxidativas. Por sua vez, as isoflavonas da soja (ISO) sao conhecidas por seu alto teor em antioxidantes. Objetivo: Avaliar o balanco pro-oxidante/antioxidante e as alteracoes morfologicas no utero de ratas ovariectomizadas (OVX) sob a influencia das ISO. Metodologia: Utilizaram-se vinte ratas Wistar com 95 dias, divididas em quatro grupos: GI-Sham (fase estro);GII-OVX; GIII-OVX tratadas com extrato concentrado de ISO (150 mg/kg/dia) por gavagem; GIV-OVX tratadas por via subcutanea com 17β-estradiol (10 µg/Kg/dia). Apos trinta dias de tratamento, as ratas foram eutanasiadas, o terco distal dos cornos uterinos fixado em formol a 10% e processado para histomorfometria e imunoistoquimica para a proteina ki-67. O restante do utero foi mergulhado em nitrogenio liquido e, posteriormente, analisado para quantificacao de especies reativas de oxigenio e nitrogenio (DCF); avaliacao da capacidade antioxidante total (TAC); e deteccao dos niveis de peroxidacao dos lipideos (TBARS). Os resultados obtidos foram submetidos a analise de variancia, seguido pelo teste de Tukey-Kramer (p≤0,005). Resultados: A espessura do endometrio e miometrio, assim como a area glandular nao diferiram significantemente entre GII e GIII, porem, mostraram-se menores em relacao a GI e GIV. O grupo GIV exibiu espessura do miometrio significantemente maior que os demais grupos. A positividade dos nucleos quanto a expressao de ki-67 em ambos o epitelio glandular e o estroma endometrial foram significativamente maiores em GI e GIV comparados com GII e GIII. O tratamento com ISO revelou menores niveis de DCF e TBARS que GII, assim como TAC significantemente maior que GI e GIV. Em GIV, apesar da diminuicao significante no TBARS, nao houve diferenca significante no DCF e foi evidenciada uma diminuicao na TAC em comparacao com GII. Conclusao: As isoflavonas melhoram os niveis de antioxidantes totais e diminuem o estresse antioxidantes totais e diminuem o estresse oxidativo, sem promover efeito trofico e proliferacao celular no utero de ratas ovariectomizadas
- ItemSomente MetadadadosEndothelial dysfunction, oxidized lipoproteins and nitric oxide in hypercholesterolemia(Federacion Bioquimica Provincia Buenos Aires, 2002-06-01) Moriel, P.; Ajzen, Sergio Aron [UNIFESP]; Bertolami, Marcelo Chiara; Abdalla, Dulcineia Saes Parra [UNIFESP]; Universidade de São Paulo (USP); Inst Dante Pazzanese Cardiol; Universidade Federal de São Paulo (UNIFESP)Endothelial dysfunction plays an important role in the pathogenesis of coronary artery disease. Plasma cholesterol, particularly that associated to LDL, has been suggested to be an important risk factor in the development of cardiovascular diseases. Moreover, LDL oxidation is a crucial event in the pathogenesis of atherosclerosis, By the other hand, a reduced bioactivity of endothelial nitric oxide ((.)NO) has been implicated in the pathogenesis of atherosclerosis. The reduction of (.)NO activity in hypercholesterolemia and in other metabolic disorders associated with atherogenesis appears to be multifactorial, However, the alterations of (.)NO production in hypercholesterolemia is still controversial. The purpose of this study was to examine the relationship of lipid peroxidation, antioxidants and nitric oxide bioavailability with the impairment of endothelium dependent vasodilation in hypercholesterolemic (HC) (n = 18) and normolipidemic subjects (N) (n = 11). Ascorbate, urate, a-tocopherol, lycopene and beta-carotene, as well as, lipid hydroxyl hydroperoxides were determined by HPLC. Endothelin was determined by ELISA. The kinetics of LDL oxidation was monitored by incubating LDL with Cu(2+). Oxysterols were determined by GC. Mode B ultrasonography was used to measure the blood flow and diameter in response to reactive hyperemia of brachial artery. The concentrations of nitrate and S-nitrosothiols in blood plasma were determined by chemiluminescence elicited by reaction of (.)NO with ozone in the (.)NO analyzer (NOA(TM280), Sievers, Corp,), The content of nitrotyrosine of blood plasma and LDL was determined by a new chemiluminescence competitive ELISA developed in our laboratory with a polyclonal antibody, Plasma ascorbate, lipid soluble antioxidants, the resistance of LDL to oxidation (lag time) and the endothelium dependent vasorelaxation were lower in HC than in N. Lidid hydroxy / hydroperoxides, endothelin, nitrate, S- nitrosothiols, total cholesterol, apo B, LDL-nitrotyrosine and LDL-cholesterol were significantly higher in HC than in N subjects. LDL cholesterol was negatively correlated to the percentage of diameter increase in response to hyperemia, The concentration of lipid soluble antioxidants was inversely related to the impairment of endothelial dependent vasodilation, In conclusion, the high level of oxidized lipids and endothelin, associated to a decrease of antioxidants and (.)NO bioavailability, can play a role in the impairment of endothelial function, which is crucial to the development of atherosclerosis in hypercholesterolemic patients.
- ItemAcesso aberto (Open Access)Gallic Acid-Loaded Gel Formulation Combats Skin Oxidative Stress: Development, Characterization and Ex Vivo Biological Assays(Mdpi Ag, 2017) Monteiro e Silva, Silas Arandas [UNIFESP]; Fioramonti Calixto, Giovana Maria; Cajado, Juliana; Antunes de Carvalho, Patricia Caballieri [UNIFESP]; Rodero, Camila Fernanda; Chorilli, Marlus; Leonardi, Gislaine Ricci [UNIFESP]Oxidative stress, which is a result of overproduction and accumulation of free radicals, is the main cause of several skin degenerative diseases, such as aging. Polyphenols, such as gallic acid, are an important class of naturally occurring antioxidants. They have emerged as strong antioxidants that can be used as active cosmetics. The purpose of this study was to develop a gallic acid-loaded cosmetic gel formulation and characterize it using rheological, mechanical, and bioadhesive tests. Its antioxidant effect in the stratumcorneumwas evaluated by a non-invasivemethod. According to the characterization tests, the formulation exhibited skin adhesiveness and pseudoplastic behavior without thixotropy, rendering it suitable for use as a cosmetic formulation. Furthermore, the non-invasive method indicated the antioxidant effect in the stratum corneum, with the global lipid peroxide reduction being 33.97 +/- 11.66%. Thus, we were able to develop a promising gallic acid-loaded gel formulation that could reduce lipid peroxides and thus combat skin oxidative stress.
- ItemAcesso aberto (Open Access)Impact of castration with or without alpha-tocopherol supplementation on the urethral sphincter of rats(Sociedade Brasileira de Urologia, 2012-04-01) Kracochansky, Mirian [UNIFESP]; Reis, Leonardo Oliveira; Lorenzetti, Fábio [UNIFESP]; Ortiz, Valdemar [UNIFESP]; Dambros, Miriam [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)OBJECTIVE: To analyze the impact of low levels of testosterone induced by orchiectomy and the effect of alpha-tocopherol supplementation on oxidative stress in the urethral sphincter. MATERIALS AND METHODS: Forty male Wistar rats weighing 250-300g were divided into four groups with 10 each: Sham group; Orchiectomy group: bilateral orchiectomy; Orchiectomy-pre-Tocopherol group: bilateral orchiectomy preceded by alpha-tocopherol supplementation for four weeks; Orchiectomy-full-Tocopherol group: bilateral orchiectomy with alpha-tocopherol supplementation for four weeks preceding the procedure and for eight weeks afterwards. At the protocol end, animals were euthanized and had the sphincter analyzed stereologically focusing on collagen and muscle fibers percentage. Oxidative stress levels were determined using 8-epi-PGF2. RESULTS: The 8-epi-PGF2 levels were statistically higher (p < 0.0003) in the Orchiectomy group compared to others groups while Sham and Orchiectomy-full-Tocopherol groups presented statistically similar values (p = 0.52). Collagen volumetric densities were significantly lower in Sham and Orchiectomy-full-Tocopherol groups (p < 0.022). Sham group presented statistically greater muscle fiber percent. CONCLUSION: Castration caused oxidative stress in the urethral sphincter complex, with increased collagen deposition. Alpha-tocopherol had a protective effect and its supplementation for twelve weeks provided the greatest protection.
- ItemSomente MetadadadosLipid peroxidation and antioxidants in hyperlipidemia and hypertension(Sociedad Biolgia Chile, 2000-01-01) Moriel, Patricia; Plavnik, Frida Liane [UNIFESP]; Zanella, Maria Teresa [UNIFESP]; Bertolami, Marcelo Chiara [UNIFESP]; Abdalla, Dulcineia Saes Parra [UNIFESP]; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP); Inst Dante Pazzanese CardiolLipid peroxidation and lipid-derived oxidized products have been implicated in the pathogenesis of a variety of human diseases. To clarify the role of oxidative stress in essential hypertension and hypercholesterolemia the in vitro oxidative susceptibility of LDL, the antioxidant status and the lipid peroxide content of blood plasma were examined in hypercholesterolemic (HC), hypertensive (H), hypercholesterolemic/hypertensive (HH) and normolipidemic/normotensive subjects (N). Plasma ascorbate and lipid-soluble antioxidants were lower, while LDL oxidizability, CE-OOH and TL-OOH were higher in H, HC, and HH groups than in the N group. No difference was observed among groups for PL-OOH and isoprostanes. In summary, the results show that: 1) lipid- and water-soluble antioxidants are lower in hypercholesterolemic and hypertensive patients as compared to normal subjects, whereas the lipid peroxide content and the LDL susceptibility to oxidation were higher; 2) total cholesterol, LDL-cholesterol, apoB and CE-OOH were negatively correlated with the content of a-tocopherol; 3) there was a positive correlation between the content of lipid-soluble antioxidants and the resistance of LDL to oxidation; and 3) CE-OOH and TL-OOH were positively correlated with total cholesterol and LDL-cholesterol.
- ItemAcesso aberto (Open Access)Serum Antioxidant Associations with Metabolic Characteristics in Metabolically Healthy and Unhealthy Adolescents with Severe Obesity: An Observational Study(Mdpi, 2018) Stenzel, Ana Paula; Carvalho, Roberta; Jesus, Patricia; Bull, Aline; Pereira, Silvia; Saboya, Carlos [UNIFESP]; Ramalho, AndreaConsidering the inadequacy of some antioxidant nutrients in severely obese adolescents, this study aimed to assess the relationship between antioxidant micronutrients status and metabolic syndrome components in metabolically healthy obesity (MHO) and unhealthy obesity (MUO). We performed an observational study in severely obese adolescents (body mass index > 99th percentile) and they were classified into MHO or MUO, according to the criteria adapted for adolescents. Anthropometric, biochemical, and clinical variables were analyzed to characterize the sample of adolescents. The serum antioxidant nutrients assessed were retinol, beta-carotene, Vitamin E, Vitamin C, zinc and selenium. A total of 60 adolescents aged 17.31 +/- 1.34 years were enrolled. MHO was identified in 23.3% of adolescents. The MHO group showed lower frequency of non-alcoholic fatty liver disease (14.3% vs. 78.3%, p < 0.001) when compared to MUO. A correlation was found between retinol and beta-carotene concentrations with glycemia (r = -0.372
- ItemSomente MetadadadosSleep deprivation induces brain region-specific decreases in glutathione levels(Lippincott Williams & Wilkins, 1998-08-24) D'Almeida, V; Lobo, L. L.; Hipolide, D. C.; Oliveira, A. C. de; Nobrega, J. N.; Tufik, S.; Universidade Federal de São Paulo (UNIFESP); Clarke Inst PsychiatRATS were deprived of sleep for 96 h by the platform technique and total glutathione (GSH tau) levels were measured in seven different brain areas. Glutathione levels were found to be significantly reduced in the hypothalamus of sleep-deprived animals when compared with large platform (-18%) or home cage (-31%) controls. Deprived rats also had reduced GSH tau levels in thalamus compared with home cage controls only. Glutathione levels did not differ among the three groups in any of the other brain areas examined. These results indicate that specific brain areas may be differentially susceptible to oxidative stress after sleep deprivation. the apparent vulnerability of the hypothalamus to these effects may contribute to some of the functional effects of sleep deprivation. (C) 1998 Lippincott Williams & Wilkins.
- ItemAcesso aberto (Open Access)Vitaminas antioxidantes e prevenção da arteriosclerose na infância(Sociedade de Pediatria de São Paulo, 2010-12-01) Boni, Adriana [UNIFESP]; Pugliese, Camila [UNIFESP]; Claudio, Cristiane Chiantelli [UNIFESP]; Patin, Rose Vega [UNIFESP]; Oliveira, Fernanda Luisa Ceragioli [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)OBJECTIVE: To review the potential antioxidant effects of vitamins A, C and E in the prevention of atherosclerosis development during childhood, emphasizing the prevention of dyslipidemia. DATA SOURCES: Bibliographic search in scientific journals, technical books and official publications of the last 20 years. Lilacs, SciElo and Medline databases were searched for articles in Portuguese, Spanish and English using a combination of the following terms: antioxidants, atherosclerosis, dyslipidemia, lipid peroxidation, childhood, vitamin A, vitamin C and vitamin E. DATA SYNTHESIS: There is an increasing prevalence of dyslipidemia in children and adolescents, probably related to changes in dietary habits and to the reduced practice of physical activities. The high plasma concentration of low-density lipoprotein (LDL-c) is a risk factor for atherosclerosis development. The consumption of nutrients rich in antioxidants, such as fruits and vegetables, is very important to prevent lipid peroxidation. The low intake of these natural antioxidants sources suggests the need for nutritional intervention to achieve the daily ingestion targets of vitamins A, C and E. Vitamin supplementation is not recommended. CONCLUSIONS: Children should be encouraged to increase ingestion of fruits and vegetables due to their potential antioxidant effect, especially in the first years of life.