Moderate-intensity exercise allows enhanced protection against oxidative stress-induced cardiac dysfunction in spontaneously hypertensive rats

The progression of myocardial injury secondary to hypertension is a complex process related to a series of physiological and molecular factors including oxidative stress. This study aimed to investigate whether moderate-intensity exercise (MIE) could improve cardiac function and oxidative stress in spontaneously hypertensive rats (SHRs). Eight-week-old male SHRs and age-matched male Wistar-Kyoto rats were randomly assigned to exercise training (treadmill running at a speed of 20 m/min for 1 h continuously) or kept sedentary for 16 weeks. Cardiac function was monitored by polygraph; cardiac mitochondrial structure was observed by scanning electron microscope; tissue free radical production was measured using dihydroethidium staining. Expression levels of SIRT3 and SOD2 protein were measured by western blot, and cardiac antioxidants were assessed by assay kits. MIE improved the cardiac function of SHRs by decreasing left ventricular systolic pressure (LVSP), and first derivation of LVP (+LVdP/dtmax and −LVdP/dtmax). In addition, exercise-induced beneficial effects in SHRs were mediated by decreasing damage to myocardial mitochondrial morphology, decreasing production of reactive oxygen species, increasing glutathione level, decreasing oxidized glutathione level, increasing expression of SIRT3/SOD2, and increasing activity of superoxide dismutase. Exercise training in SHRs improved cardiac function by inhibiting hypertension-induced myocardial mitochondrial damage and attenuating oxidative stresses, offering new insights into prevention and treatment of hypertension.

The effects of an experimentally induced unilateral varicose ovarian vein on the activities of anti-oxidant enzymes in an adult rat ovary / Efectos de la inducción experimental unilateral de una vena ovárica varicosa sobre las actividades de las enzimas anti-oxidantes en ovarios de ratas adultas

In this study, we aim to examine effects of an experimentally induced unilateral varicose ovarian vein on the activities of anti-oxidant enzymes in an adult rat ovary. In this experimental study, a total of 30 adult female Wistar albino rats were divided into three groups. 10 rats in group 1 as the varicocele group, 10 rats in group 2 as the control group and 10 rats in group 3 as the sham group, that underwent a sham operation and. Anti-oxidant assays were assessed via specific assay kits. Statistical analysis was performed using the one way ANOVA and Tukey's tests were used for post hoc multiple comparisons, P<0.05 was considered statistically significant. The effects of the unilateral varicosity was more evident on the left side when compared to the right side as all activities of the anti-oxidant assayed were significantly reduced, P 0.05 when compared to the right side. Also, in this present study, the effect of the unilateral varicose vein was bilateral as there were no significant differences recorded between the two sides. Finally the result of this study shows that varicocele may lead to female infertility through various factors that includes reduction in the activities of anti-oxidant enzymes.

En este estudio, nuestro objetivo fue examinar los efectos de la inducción experimental unilateral de una vena ovárica varicosa en la actividad de enzimas antioxidantes en un ovario de rata adulta. Un total de 30 ratas albinas Wistar, hembras adultas, se dividieron en tres grupos. Diez ratas en el grupo 1 (grupo varicocele), diez ratas en el grupo 2 (grupo de control) y diez ratas en el grupo 3 (grupo de tratamiento simulado), que se sometió a una operación simulada. Ensayos con anti-oxidantes se evaluaron a través de kits de ensayo específicos. El análisis estadístico se realizó mediante ANOVA de una vía y las pruebas de Tukey fueron utilizadas para comparaciones múltiples Post Hoc, siendo el P<0,05 considerado como estadísticamente significativo. Los efectos de la varicosidad unilateral fue más evidente en el lado izquierdo cuando fue comparada con el lado derecho en todas las actividades del ensayo con anti-oxidante que se redujeron significativamente, el P 0,05 cuando se compara con el lado derecho. Asimismo, en el presente estudio, el efecto de la vena varicosa unilateral fue bilateral ya que no hubo diferencias significativas registradas entre las dos partes. Por último, el resultado de este estudio muestra que el varicocele puede conducir a la infertilidad femenina a través de diversos factores que incluye la reducción en la actividad de las enzimas antioxidantes.

Sistema antioxidante enzimático e indicadores de daño oxidativo en pacientes diabéticos tipo 2 / Antioxidant enzymatic system and oxidative damage indicators in patients with type 2 diabetes

Several biological processes are involved in the oxidative stress present in diabetes mellitus; among them we can find glucose autooxidation, proteins glycation and decreased antioxidant defenses. Free radicals yielded at mitochondrial level could be a trigger to unchain the vicious circle of the oxidative stress in diabetes mellitus. Aims: to determine antioxidant system’s alterations and indicators of oxidative damage on lipids and proteins in patients with type II Diabetes and a control group. Materials and Methods: It was analyzed 120 serum samples; 60 from patients that suffer type II diabetic from endocrinology surgery belonging “Casa de atención al paciente diabético”in Santa Clara, Villa Clara and 60 samples from healthy individuals used as control group. Spectrofotometric techniques were used to assess levels of Superoxide dismutase and Catalase activity as well as concentrations of reduced glutathione, malonildialdehide and advanced products of proteins Oxidation. Results were compared using the statistical software SPSS. Results: Diabetes type 2 patients showed decreased of Superoxide Dismutase and Catalase enzymatic activity (p = 0,003) and (p = 0,013) respectively as well as and reduced Glutathione levels (p = 0,038). Malondialdehide and Advanced Products of Proteins Oxidation were increased (p = 0,000) in diabetics patients compared with control group. Conclusions: it was found redox alterations in patients that suffer type 2 Diabetes. These alterations are evidenced by a reduced antioxidant enzymatic system and damage on macromolecules such as lipids and proteins...

Superoxide dismutases and glutaredoxins have a distinct role in the response of Candida albicans to oxidative stress generated by the chemical compounds menadione and diamide

To cope with oxidative stress, Candida albicans possesses several enzymes involved in a number of biological processes, including superoxide dismutases (Sods) and glutaredoxins (Grxs). The resistance of C. albicans to reactive oxygen species is thought to act as a virulence factor. Genes such as SOD1 and GRX2, which encode for a Sod and Grx, respectively, in C. albicans are widely recognised to be important for pathogenesis. We generated a double mutant, Δgrx2/sod1, for both genes. This strain is very defective in hyphae formation and is susceptible to killing by neutrophils. When exposed to two compounds that generate reactive oxygen species, the double null mutant was susceptible to menadione and resistant to diamide. The reintegration of the SOD1 gene in the null mutant led to recovery in resistance to menadione, whereas reintegration of the GRX2 gene made the null mutant sensitive to diamide. Despite having two different roles in the responses to oxidative stress generated by chemical compounds, GRX2 and SOD1 are important for C. albicans pathogenesis because the double mutant Δgrx2/sod1 was very susceptible to neutrophil killing and was defective in hyphae formation in addition to having a lower virulence in an animal model of systemic infection.

Efeito do exercício físico e do polimorfismo T-786C na pressão arterial e no fluxo sanguíneo de idosas / Effect of physical activity and t-786C polymorphism in blood pressure and blood flow in the elderly / Efecto del ejercicio físico y del polimorfismo T-786C en la presión arterial y en el flujo sanguíneo de añosas

FUNDAMENTO: O polimorfismo T-786C do gene da sintetase do óxido nítrico endotelial (eNOS) e a produção de ânion superóxido podem diminuir a produção e biodisponibilidade do óxido nítrico, comprometendo o grau de vasodilatação, podendo este efeito ser revertido pelo exercício físico. OBJETIVO: Investigar a influência do treinamento aeróbico e do polimorfismo T-786C nas concentrações dos metabólitos do óxido nítrico (NOx), no fluxo sanguíneo (FS) e na pressão arterial (PA). MÉTODOS: Trinta e duas idosas pré-hipertensas (59 ± 6 anos) foram separadas em dois grupos de acordo com o polimorfismo T-786C (TT e TC+CC). Foram analisadas as concentrações de NOx (plasma) e fluxo sanguíneo por pletismografia de oclusão venosa em repouso, 1, 2 e 3 minutos pós-oclusão (FS-0, FS-1, FS-2, FS-3, respectivamente). As avaliações foram realizadas antes e após 6 meses de um programa de exercício aeróbico. RESULTADOS: Nas avaliações pré-treinamento, os níveis de NOx foram menores no grupo TC+CC em relação ao grupo TT. O grupo TT apresentou correlações entre NOx e FS-0 (r = 0,6) e pressão arterial diastólica (PAD) e FS-0 (r = -0,7), porém nenhuma correlação foi encontrada no grupo TC+CC. Nas avaliações pós-treinamento, ocorreram correlações entre NOx e FS-0 (r = 0,6) e nas mudanças do NOx e PAD (r = -0,6) no grupo TT. Também foram obtidas correlações entre PAD e FS-1 (r = -0,8), PAD e FS-2 (r = -0,6), PAD e FS-3 (r = -0,6), nas mudanças entre NOx e FS-1 (r = 0,8) e mudanças do NOx e PAD (r = -0,7) no grupo TC+CC. CONCLUSÃO: Conclui-se que 6 meses de exercício aeróbico podem contribuir para aumentar as relações existentes entre NO, PA e FS em idosas portadores do alelo C.

BACKGROUND: The T-786C polymorphism of the gene for endothelial nitric oxide synthase (eNOS) and superoxide anion production may reduce production and bioavailability of nitric oxide, affecting the degree of vasodilation. This effect can be reversed by exercise. OBJECTIVE: To investigate the influence of aerobic training and T-786C polymorphism in the concentrations of nitric oxide metabolites (NOx) in blood flow (BF) and blood pressure (BP). METHODS: Thirty-two elderly pre-hypertensive women (59 ± 6 years old) were divided into two groups according to the T-786C polymorphism (TT and TC + CC). We analyzed the concentrations of NOx (plasma) and blood flow by venous occlusion plethysmography at rest, 1, 2 and 3 minutes post-occlusion (BF-0, BF-1 BF-2 BF-3, respectively). Evaluations were performed before and after 6 months of a program of aerobic exercise. RESULTS: In the pre-training evaluations, NOx levels were lower in TC + CC group than in TT group. The TT group showed correlations between NOx and BF-0 (r = 0.6) and diastolic blood pressure (DBP) and BF-0 (r = -0.7), but no correlation was found in TC + CC group. In the post-training evaluations, there were correlations between NOx and BF-0 (r = 0.6) and the changes in NOx and DBP (r = -0.6) in TT group. There were also correlations between DBP and BF-1 (r = -0.8), DBP, and BF-2 (r = -0.6), DBP, and BF-3 (r = -0.6), in the changes between NOx and BF-1 (r = 0.8) and changes in NOx and DBP (r = -0.7) in TC + CC group. CONCLUSION: It was concluded that 6 months of aerobic exercise can increase the relationship between NO, BP and BF in elderly of allele C carriers.

FUNDAMENTO: El polimorfismo T-786C del gen de la sintetasa del óxido nítrico endotelial (eNOS) y la producción de anión superóxido pueden disminuir la producción y biodisponibilidad del óxido nítrico, comprometiendo el grado de vasodilatación, pudiendo este efecto ser revertido por el ejercicio físico. OBJETIVO: Investigar la influencia del entrenamiento aeróbico y del polimorfismo T-786C en las concentraciones de los metabolitos del óxido nítrico (NOx), en el flujo sanguíneo (FS) y en la presión arterial (PA). MÉTODOS: Treinta y dos añosas prehipertensas (59 ± 6 años) fueron separadas en dos grupos de acuerdo con el polimorfismo T-786C (TT y TC+CC). Fueron analizadas las concentraciones de NOx (plasma) y flujo sanguíneo por pletismografía de oclusión venosa en reposo, 1, 2 y 3 minutos post oclusión (FS-0, FS-1, FS-2, FS-3, respectivamente). Las evaluaciones fueron realizadas antes y después de 6 meses de un programa de ejercicio aeróbico. RESULTADOS: En las evaluaciones pre entrenamiento, los niveles de NOx fueron menores en el grupo TC+CC en relación al grupo TT. El grupo TT presentó correlaciones entre NOx y FS-0 (r = 0,6) y presión arterial diastólica (PAD) y FS-0 (r = -0,7), sin embargo ninguna correlación fue encontrada en el grupo TC+CC. En las evaluaciones post entrenamiento, ocurrieron correlaciones entre NOx y FS-0 (r = 0,6) y en los cambios del NOx y PAD (r = -0,6) en el grupo TT. También fueron obtenidas correlaciones entre PAD y FS-1 (r = -0,8), PAD y FS-2 (r = -0,6), PAD y FS-3 (r = -0,6), en los cambios entre NOx y FS-1 (r = 0,8) y cambios del NOx y PAD (r = -0,7) en el grupo TC+CC. CONCLUSIÓN: Se concluye que 6 meses de ejercicio aeróbico pueden contribuir a aumentar las relaciones existentes entre NO, PA y FS en añosas portadoras del alelo C.

Wound healing activity of Ocimum sanctum Linn with supportive role of antioxidant enzymes.

The present study was performed to evaluate the wound healing and antioxidant effect of aqueous extract of Ocimum sanctum Linn. (O. sanctum) in rats. Albino rats of either sex were divided into 2 groups. Group I: Wounded control rats; Group II: Wounded rats administered O. sanctum aqueous extract. Wound breaking strength in incision wound model, epithelization period and percent wound contraction in excision wound model were studied. Using dead space wound model, granulation tissue breaking strength, granulation tissue dry weight, hydoxyproline level in dry granulation tissue, superoxide dismutase (SOD) and catalase levels in wet granulation tissue were estimated in both the groups. Increased wound breaking strength, decreased epithelization period, increased percent wound contraction, increased granulation tissue weight and hydroxyproline concentrations were observed. The increased activity of antioxidant enzymes such as SOD, catalase level in extract treated group compared to controls. Granulation tissue was subjected to histopathological examination to determine the pattern of lay-down for collagen using Haematoxylin and Eosin stains which confirm the results. Owing to wound healing and antioxidant activities, O. sanctum may be useful in the management of abnormal healing such as keloids and hypertrophic scars.

Amplifying the manganese scavenging potential of Streptococcus zooepidemicus to reactive oxygen species during production of hyaluronic acid

Streptococcus zooepidemicus (SZ) is an aerotolerant bacteria and its ability to survive under reactive oxidant challenge raises the question of the existence of a defense system. Thus growth, hyaluronic acid (HA) and hydrogen peroxide (H2O2) production by SZ in the presence of increasing concentration of Mn2+ were studied. The results suggested that the tested strain supported growth and HA production in cultures treated with 1 and 10 mM of Mn2+ regardless of H2O2 presence in the medium. This showed that SZ have acquired elaborate defense mechanisms to scavenge oxygen toxicity and thus protect cells from direct and indirect effect of this radical. In contrast, cells treated with 25 mM Mn2+ were sensitive, in which, the HA production was reduced considerably. Thus showing that the oxygen scavenger systems of the cells may be fully saturated at this concentration.

Antioxidantes y envejecimiento cutáneo / Antioxodants and cutaneous aging

Las formulaciones disponibles actualmente para uso dermatológico, basadas en sustancias antioxidantes tales como vitaminas C y E, entre otras, abundan con promesas de revertir el envejecimiento cutáneo. En el presente trabajo se realiza una revisión de los sistemas antioxidantes cutáneos, de la relación entre envejecimiento y daño oxidativo, así como de la evidencia disponible en cuanto al tratamiento con antioxidantes. La intención de este artículo es que el dermatólogo comprenda las bases fisiológicas de acción de los antioxidantes, para poder juzgar su utilidad con una mirada crítica

Lipid peroxidation and diabetic retinopathy.

The high level of glucose in blood for a long duration is the main cause of the development of retinopathy. So yearly screening of patients newly diagnosed with NIDDM diabetes is recommended because rare cases of treatable diabetic retinopathy have occurred early in one course of NIDDM diabetes. Hyperglycaemia leads to non-enzymatic glycosylation of proteins and HbA1C was found increased. Antioxidants such as GSH and SOD level is found decreased in retinopathy conditions due to the higher lipid peroxidation, which is evident from high MDA and DC values. So it can be clearly stated that increase in the free radical by hyperglycaemia, lipid peroxidation and advanced glycosylation endproducts along with decreased antioxidants are the causative agents for the development of retinopathy.

Indicadores del metabolismo oxidativo en primates no humanos viejos / Levels oxidative metabolism markers during aging in non-human primates

En condiciones fisiológicas las células aeróbicas producen cantidades de Especies Reactivas de Oxígeno. La supervivencia celular depende del balance entre los procesos oxidativos y las defensas antioxidantes. Esta interacción determina si la célula se encuentra en estrés oxidativo o no. Recientes estudios sugieren que una reducida capacidad en el metabolismo oxidativo así como estados proinflamatorios contribuyen a cambios neurodegenerativos relacionados con la edad en los humanos. Por tal motivo en el presente estudio nosotros comparamos los niveles séricos de la actividad de la superóxido dismutasa (SOD), Catalasa (CAT) y también los niveles de malonildialdehido (MDA) y el factor de necrosis tumoral a (TNFa) en primates no humanos jóvenes y viejos. Nuestros resultados sugieren relación entre las alteraciones del metabolismo oxidativo con los cambios neurodegenerativos que ocurren en los monos.

Mimics of copper proteins: structural and functional aspects

The importance of copper as an essential element can be estimated by the wide range of copper proteins and enzymes playing different roles in biological systems. In the last decades many bioinorganic studies were developed on mimetic complexes of copper-dependent proteins, in order to verify the interrelations between structural and functional properties of active copper centers. Among the most studied copper ion ligand, diimine compounds have deserved special attention due their flexibility, facility of preparation, and ability to stabilize both oxidation states of this metal. In our laboratory, we have been investigating some Schiff base copper complexes as mimics of different proteins, with emphasis on functional aspects, trying to elucidate mechanisms of reaction, based on proposed intermediary species, in addition to molecular shapes. Particularly, mimics of the copper-zinc superoxide dismutase, and of monooxigenases and oxidases exhibiting dicopper sites are discussed in this work.

Biochemical aspects of cellular antioxidant systems

Aerobic life is characterized by a steady generation of reactive oxygen species balanced by a similar rate of their consumption by antioxidants. To maintain homeostasis, there is a requirement for the continuous regeneration of antioxidant capacity, and if this is not met, oxidative stress occurs, resulting in pathophysiological events. Cellular protection against oxidative stress is organized at multiple levels. Defense strategies include prevention, interception, replacement, and repair. These mechanisms are coupled to the intermediary metabolism for a continuous supply of energy, reducing equivalents, and precursors, and depend on the dietary supply of metabolic fuels and essential molecules to allow an optimal cellular functioning

Possible effect of air pollutants (Mexico City) on superoxide dismutase activity and serum lipoperoxides in the human adult

The action of air pollutants, through their constituents, (O3, NO2, tobacco smoke) are capable of causing damage due to their lipoperoxidative properties or, indirectly, by inducing production of free radicals. As a consequence of photochemical processes, the ozone levels in the atmosphere of Mexico City are generally higher (mean of 0.325 ppm; period between 1987 - 1992) and may be harmful to health. Sixty two volunteers (medical doctors), aged 27-32 years, were divided into three groups. Group A was composed of those persons /17) who had never lived in Mexico City; a second group (B) (21) had recently arrived in Mexico City (1-8 days); and a third group (C) (24) who had permanently resided in mexico City. Serum was obtained from fresh whole blood. Superoxide dismutase (SOD) activity and thiobarbituric acid-reactive materials were higher in group B while chromolipids and the serum inhibitory capacity (for lipoperoxidation) was higher in group C. The acute exposure to pollutants in group B apparently may have induced SOD as an antioxidant defense and was responsible for the increased level of TBA reactive material. In group C, the significant finding is better antioxidative defenses and slightly higher chromolipids

Oxygen detoxifying enzymes in uremic patients

Orygen free radical is a highly toxic agent which is liberated during many metabolic processes. This toxic product is detoxified through the oxygen detoxifying enzyme system, superoxide dismutase [S.O.D.], catalase and glutathione peroxidase. The above mentioned enzymes were found to be elevated in the early stage of chronic renal failure and the activity decreased with the development of the disease. The early affected enzyme is glutathione peroxidase

Respuesta pulmonar tardia a la infusion de ácidos grasos libres: rol del radical superóxido / Late pulmonary response to the infusion of free fatty acids: role of the superoxide radical

La infusión intravenosa de ácidos grasos libres (AGL) en conejos producem edema pulmonar por aumento de la permeabilidad, reacción inflamatoria y aumento del surfactante alveolar. Con el objetivo de definir el rol del anión super-óxido (O2-) en el daño pulmonar difuso producido por EGL, se evaluó el efecto de la superóxido dismutasa (SOD). Se estudiaron 4 series de conejos que recibieron: a) AGL (n = 6): 10 mg AGL/Kg/min.i.v. durante 15 minutos. b) Vehículo de AGL (n=5)i.v. durante 15 y 25 minutos AGL + SOD (mg/Kg i.v. durante 15 y 25 minutos respectivamente (n = 6); d) Vehículo + SOD durante 15 y 25 minutos respectivamente (n = 7). Al cabo de 96 horas los conejos fueron sacrificados, determinándose en el lavado bronquioalveolar: proteínas, fosfatidilcolina disaturada (DPPC) y el recuento celular. Hubo un aumento significativo de DPPC del recuento de células en todas las seires en comparación a la serie vehículo (b). SOD no modificó las alteraciones inducidas por AGL, aunque "per se" aumentó la DPPC y el recuento de células en el LBA. La histología pulmonar mostró edema perivascular e intra-alveolar en los animales inyectados con AGL. Estas alteraciones fueron francamente disminuidas por la SOD. Estos resultados sugieren que el O2- tendria un rol sólo secundario en el daño pulmonar difuso por AGL, ya que SOD protegió solo parcialmente al pulmón de este daño