Application of propolis extract, nanovitamin C and nanovitamin E to prevent alveolar osteitis after impacted lower third molar surgery. A randomized, double-blind, split-mouth, pilot study / Aplicación de extracto de propóleo, nanovitamina C y nanovitamina E para prevenir la osteítis alveolar después de una cirugía de terceros molares inferiores retenidos. Un estudio piloto aleatorizado, doble ciego y de boca dividida

Background: Propolis has anti-inflammatory, analgesic and healing properties. The purpose of this study was todetermine whether a gel containing 2% of propolis extract, 0.2% of ascorbic acid and 0.2% of tocopherol acetateis effective in preventing surgical complications related to impacted lower third molar extractions.Material and Methods: A randomized, double-blind, split-mouth study was performed. Fifteen patients were re-cruited who needed bilateral impacted lower third molar extractions with a similar surgical difficulty. A test orplacebo gel was administered randomly inside post-extraction sockets. Each patient was instructed to apply thegel 3 times/day in the surgical wound for a week. After a month, the contralateral third molar was extracted, andthe opposite gel applied. The following parameters were diagnosed/evaluated and then recorded: alveolar osteitisfollowing Blum’s criteria, swelling and trismus at day one, two, three and seven post-intervention, wound healingat day 7 post-intervention, and postoperative pain using a visual analog scale, as well as, the number of analgesicpill intake.Results: A total of twenty-six surgical procedures were performed in 13 patients (mean age 20.67±2 years). Alveo-lar osteitis was reported in 3 patients from the placebo group (23.1%) and none in the test group (0%) (p=0.25). Nostatistically significant differences were reported in swelling, trismus, wound healing or analgesic pill consump-tion between two groups. But statistically lower postoperative pain during the 7 days after surgical extractionswas found according to visual analog scale in test group compared to the placebo group (p=0.007). No side effectswere reported.(AU)

Anti-allergic function of alpha-Tocopherol is mediated by suppression of PI3K-PKB activity in mast cells in mouse model of allergic rhinitis

BACKGROUND: Alpha-Tocopherol (alpha -TCP), one major form of vitamin E, has been known as a treatment for airway allergic inflammation. However, the role and mechanism of alpha-TCP in treating allergic rhinitis remains unclear. OBJECTIVE: In this study we examined the inhibitory function of alpha-TCP in a mouse model of allergic rhinitis. METHODS: Allergic phenotype was examined by hematoxylin and eosin staining. Total IgE, OVA-specific IgE, OVA-specific IgG1 and OVA-specific IgG2a levels were examined by ELISA. mRNA expression was measured by qPCR, protein levels were examined by Western Blot. RESULTS: Histological analysis of the nasal membranes revealed that there was a significant reduction in inflammatory cells appearance in cross-sections in alpha-TCP treatment of Ovalbumin (OVA)-sensitized mice compared to OVA sensitized animals. In addition, eosinophils were significantly reduced in nasal mucosa of alpha-TCP treatment of OVA-sensitized mice compared to the OVA group. Lower total IgE, OVA-specific IgE, OVA-specific IgG1 and OVA-specific IgG2a levels were found in alpha-TCP treatment of OVA-sensitized mice compared to the OVA group. Furthermore, we found that the subepithelial distribution of tryptase positive mast cells was reduced in the alpha-TCP treatment of OVA-sensitized mice. More importantly, the PI3K-PKB pathway was suppressed by alpha-TCP in mast cells. CONCLUSIONS: Our results demonstrated that α-TCP-mediated suppression of PI3K-PKB activity in mast cells is a potential mechanism of anti-allergic function of alpha-TCP

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p66shc-mediated toxicity of high-dose alfa-tocopherol in renal proximal tubule cells

α-Tocopherol (TOC) is a widely used supplement known for its role as an antioxidant. Previously, we have shown that TOC elicits adaptive responses by upregulating the ERK/CREB/HO-1 pathway, which depends on its concentration in cultured renal proximal tubule cells (RPTCs). This suggests that high-dose TOC (hTOC) may elicit adverse effects via inflicting oxidative stress. Since the pro-oxidant p66shc is a major mediator of oxidant injury in various models of renal toxicants, we tested the hypothesis that hTOC elicits renal toxicity through activation of p66shc and consequent oxidative stress. RPTCs (NRK52E) were treated with high-dose TOC (hTOC; 400 nM) in cells where expression or mitochondrial cytochrome c-binding of p66shc was manipulated by genetic means. Intracellular production of reactive oxygen species (ROS), mitochondrial depolarization, and cell viability was also determined. Additionally, activation of the pro-survival ERK/CREB/HO-1 signaling and the p66shc promoter was determined via reporter luciferase assays. hTOC decreased cell viability via increasing ROS-dependent mitochondrial depolarization and suppressing the pro-survival ERK/CREB/HO-1 pathway via transcriptional activation of p66shc. Conversely, either knockdown of p66shc, mutation of its mitochondrial cytochrome c-binding site, or overexpression of ERK or HO-1 ameliorated adverse effects of hTOC and restored the pro-survival signaling. The pro-oxidant p66shc plays dual role in toxicity of high-dose TOC: it provokes oxidative stress and suppresses adaptive responses (AU)

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Alpha-Tocopherol protects renal cells from nicotine- or oleic acid-provoked oxidative stress via inducing heme oxygenase-1

Smoking and obesity increases renal oxidative stress via nicotine (NIC) or free fatty acid such as oleic acid (OA) but decreases levels of the vitamin E-derivative alpha-tocopherol (TOC), which has shown to stimulate the antioxidant system such as heme oxygenase-1 (HO-1). Hence, we hypothesized that supplementation of TOC may protect renal proximal tubules from NIC- or OA-mediated oxidative stress by upregulating the HO-1 gene. NIC- or OA-dependent production of reactive oxygen species (ROS) was determined in the presence or absence of various pharmacologic or genetic inhibitors that modulate HO-1 activation and enhancer elements in the HO-1 promoter such as the antioxidant response element (ARE) and the cAMP-response element (CRE) in renal proximal tubule cells (NRK52E). Activity of the HO-1 promoter, the ARE and the CRE was determined in luciferase assays. We found that pre- or posttreatment with TOC attenuated NIC- or OA-dependent ROS production that required HO-1 activation. TOC activated the HO-1 promoter via the CRE but not the ARE enhancer through the extracellular signal-regulated kinase (ERK) and protein kinase A (PKA). Consequently, inhibitors of ERK, PKA, or CRE activation mitigated beneficial effects of TOC on NIC- or OA-mediated ROS production. Hence, vitamin E supplementation-via induction of the cytoprotective HO-1-may help to reduce renal oxidative stress imposed by smoking or obesity

Alterations in the extracellular catabolism of nucleotides and platelet aggregation induced by high-fat diet in rats: effects of alpha-tocopherol

The aim of this study was to assess whether alfa-tocopherol administration prevented alterations in the ectonucleotidase activities and platelet aggregation induced by high-fat diet in rats. Thus, we examined four groups of male rats which received standard diet, high-fat diet (HFD), α-tocopherol (α-Toc), and high-fat diet plus α-tocopherol. HFD was administered ad libitum and α-Toc by gavage using a dose of 50 mg/kg. After 3 months of treatment, animals were submitted to euthanasia, and blood samples were collected for biochemical assays. Results demonstrate that NTPDase, ectonucleotide pyrophosphatase/phosphodiesterase, and 5'-nucleotidase activities were significantly decreased in platelets of HFD group, while that adenosine deaminase (ADA) activity was significantly increased in this group in comparison to the other groups (P < 0.05). When rats that received HFD were treated with α-Toc, the activities of these enzymes were similar to the control, but ADA activity was significantly increased in relation to the control and α-Toc group (P < 0.05). HFD group showed an increased in platelet aggregation in comparison to the other groups, and treatment with α-Toc significantly reduced platelet aggregation in this group. These findings demonstrated that HFD alters platelet aggregation and purinergic signaling in the platelets and that treatment with α-Toc was capable of modulating the adenine nucleotide hydrolysis in this experimental condition

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Consumo alimentar e níveis plasmáticos de vitaminas antioxidantes em crianças e adolescentes obesos com e sem doença hepática gordurosa não alcoólica / Food intake and plasma levels of antioxidant vitamins in obese children and adolescents with and without non-alcoholic fatty liver disease

Objetivo: Comparar o consumo alimentar e os ní- veis séricos de vitaminas antioxidantes entre crianças e adolescentes obesos com e sem doença hepática gordurosa não alcoólica. Métodos: Estudo transversal observacional, composto por 37 crianças e adolescentes obesos atendidos em primeira consulta em um Ambulatório de Pediatria de um Hospital Universitário do interior de Minas Gerais, Brasil. Os indivíduos foram divididos em dois grupos após exame de ultrassonografia, sendo um grupo composto por crianças obesas com esteatose, e outro por crianças obesas sem a doença. Os grupos foram comparados quanto a parâmetros antropométricos, bioquímicos e de consumo alimentar. Verificou-se também o risco de determinada alteração nos referidos parâmetros significar maior chance para desenvolvimento de esteatose hepática. Resultados: O grupo de obesos com esteatose apresentou menor ingestão dietética das vitaminas antioxidantes A, C e E, e redução dos níveis séricos de betacaroteno e alfa tocoferol, quando comparado ao grupo de crianças obesas sem esteatose, contudo, não houve diferença estatística entre os grupos. Somente os níveis séricos de ácido ascórbico apresentaram redução significativa no grupo com esteatose (0,94 mg/dL ± 0,21), em relação ao grupo sem a doença (1,28 mg/dL ± 0,34). As alterações bioquímicas e de consumo alimentar de vitaminas antioxidantes não demonstraram associação significativa com risco de desenvolvimento da doença. Conclusão: Hábitos alimentares de crianças obesas com e sem esteatose evidenciam um consumo deficiente de vitaminas antioxidantes, aliado a reduções nos níveis séricos. Essas alterações ainda não podem ser consideradas fatores de risco para desenvolvimento da doença, mas sugerem maior cuidado nutricional para evitar a progressão da esteatose simples para esteato hepatite e cirrose hepática. A intervenção no estilo de vida se faz necessária, além de novos estudos visando um correto planejamento dietoterápico (AU)

Objective: To compare dietary intake and serum levels of antioxidant vitamins among obese children and adolescents with and without non-alcoholic fatty liver disease. Methods: An observational cross-sectional study composed by 37 obese children and adolescents from the first visit in a Pediatric Outpatient Clinic of a university hospital in Minas Gerais, Brazil. The subjects were divided into two groups after ultrasound examination, with a group of obese children with steatosis, and another for obese children without the disease. The groups were compared regarding anthropometric, biochemical and food consumption parameters. There was also the risk of certain changes in these parameters mean greater chance for development of hepatic steatosis. Results: The group of obese patients with steatosis had lower dietary intake of antioxidant vitamins A, C and E, and reduced serum levels of beta-carotene and alpha tocopherol compared to the obese group without steatosis, however, there was no statistical difference between the groups. Only serum ascorbic acid levels were significantly reduced in the group with steatosis (0.94 mg / dL ± 0.21) compared to those without the disease (1.28 mg / dL ± 0.34). Thus, biochemical and dietary intake of antioxidant vitamins changes were not significantly associated with risk of developing the disease. Conclusion: Feeding habits of obese children with and without steatosis show a deficient intake of antioxidant vitamins, combined with reductions in serum levels. These changes can’t yet be considered risk factors for developing the disease, but suggest greater nutritional care to prevent the progression of simple steatosis to steatohepatitis hepatitis and liver cirrhosis. The lifestyle intervention is needed, and new studies to a correct diet therapy planning (AU)

Alpha-tocopherol in the brain tissue preservation of stroke-prone spontaneously hypertensive rats

Oxidative stress has an important role in neuronal damage during cerebral ischemia and can lead to cognitive and behavioral impairment. Alpha-tocopherol, a powerful antioxidant, may be able to preserve neuronal tissue and circumvent neurological deficits. Thus, this study aimed to investigate the influence of alpha-tocopherol in the preservation of brain tissue and the maintenance of memory formation in stroke-prone spontaneously hypertensive rats (SHRSP). To achieve this aim, twenty-four 15-week-old male SHRSP rats were separated into the following four groups (n = 6 each) that received different treatments over a 4-week period: the alpha-tocopherol group, the control group, the L-NAME group, and the L-NAME + alpha-tocopherol group. We evaluated the physiological parameters (body weight, diuresis, and food and water intake), an oxidative stress marker (malondialdehyde levels), and neurological responses (the Morris Water Maze and Novel Objects Recognition tests). Afterwards, the brains were removed for histopathological analysis and quantification of the number of cells in the hippocampus. Statistically, the alpha-tocopherol group demonstrated better results when compared to all groups. The data indicated a reduction in oxidative stress and the preservation of neurological responses in groups treated with alpha-tocopherol. In contrast, the L-NAME group exhibited increased malondialdehyde levels, impairment of neurological responses, and several hippocampus tissue injuries. The others groups exhibited nerve tissue changes that were restricted to the glial nodes. No significant alterations were observed in the physiologic parameters. Based on these findings, we suggest that alpha-tocopherol can prevent stroke, preserve the structure of the hippocampus, and maintain both memory and cognition functions

Alpha-tocopherol ameliorates oxidative renal insult associated with spinal cord reperfusion injury

Ischemic-reperfusion procedures targeting a specific organ often results in remote multiple organ injuries mediated possibly by heightened oxidative stress levels. As the kidney is one of the most vulnerable organs for ischemic oxidative stress, the aim of the present study was to confirm the occurrence of renal complication secondary to spinal cord ischemic-reperfusion injury (SC-IRI) induced by aortic clamping. The study also investigated the possible prophylactic effect of long-term administration of α-tocopherol (Alpha -TOL) against high level of renal oxidative stress and inflammatory processes induced by SC-IRI. In this study, a total of 60 male Sprague-Dawley rats were randomly divided into five equal groups: C group underwent no surgery; CE group received α-TOL 600 mg/kg intramuscular twice weekly for 6 weeks; S group were subjected to laparotomy without clamping of the aorta; SE group were handled as S group and treated with Alpha-TOL as group CE; SC-IRI group were subjected to laparotomy with clamping of the aorta just above the bifurcation of the aorta for 45 min, then the clamp was released for 48 h for reperfusion. SC-IRIE group was subjected to IRI as in group SC-IRI and was injected with Alpha-TOL in the same dose and route as Alpha-TOL-treated control group. SC-IRI resulted in increases in serum creatinine, blood urea nitrogen, plasma nitrite/nitrate level, serum tumor necrosis factor alpha, renal tissue homogenate level for malondialdehyde, superoxide dismutase and prostaglandin E2. Long-term prophylactic treatment with α-TOL resulted in amelioration of the renal functional disturbances and all measured parameters of oxidative stress and inflammation. Ischemic reperfusion injury of the spinal cord induced some remote renal functional disturbances although some of the observed changes may have resulted from decreased renal blood flow due to the hypotension induced during the procedure. Prophylactic long-term α-TOL administration guards against the renal function disturbances an effect that can be attributed, at least partially, to improvement of the renal pro-oxidant/antioxidant balance and inhibition of the inflammatory processes

La exposición aguda a altitud previene el estrés oxidativo por una movilización del alfa-tocoferol plasmático / Acute exposure to moderate altitude prevents oxidative stress by a plasmatic alpha-tocopherol mobilization

Introducción: Existe gran controversia sobre el efecto de la hipoxia en el estatus oxidativo de deportistas; por otra parte, la mayoría de estudios analizan los mecanismos de adaptación tras un periodo de aclimatación y no contemplan el efecto de las exposiciones agudas. Así, nuestro estudio pretende comprobar el efecto del ejercicio y la exposición aguda a una altitud moderada sobre el estrés oxidativo en nadadores. Material y método: Diez nadadores entrenados (5 mujeres, 5 hombres) realizaron dos sesiones idénticas de entrenamiento de 90 minutos, una a 630 m (normoxia) y otra a 2320 m de altitud (hipoxia); ambas se ajustaron para generar valores de lactato ligeramente superiores al umbral anaeróbico. Se extrajeron 5 ml de sangre en reposo y tras el esfuerzo. Las muestras fueron centrifugadas para la obtención de plasma y congeladas a -80ºC. Como marcador de peroxidación lipídica se determinaron concentraciones de hidroperóxidos y sustancias reactivas al ácido tiobarbitúrico (TBARS). Como mecanismo antioxidante no enzimático se cuantificó el alfa-tocoferol. Las comparaciones de medias se realizaron con una ANOVA de un factor. Resultados: La exposición a hipoxia produjo un descenso significativo de TBARS (20,78±8,36 nmol/ml, p<0,03) y, tras el esfuerzo, de hidroperóxidos (20,78±8,36 nmol/ml, p<0,03) en hombres. En nadadores de ambos sexos, el alfa-tocoferol disminuyó significativamente debido a la hipoxia (hombres: 23,06±4,26 nmol/ml, mujeres: 19,51±4,26 nmol/ml, p<0,001). En normoxia, las mujeres presentaron menor concentración de TBARS (20,54±8,36 nmol/ml, p<0,03) e hidroperóxidos (2,16±0,87 nmol/ml, p<0,03) que los hombres. La sesión de entrenamiento no modificó dichas variables. Conclusiones: En estudios previos demostramos una movilización de antioxidantes no enzimáticos desde plasma a tejidos muscular y hepático en situaciones de estrés oxidativo. Concluimos que una exposición aguda a altitud moderada podría prevenir el estrés oxidativo en nadadores debido a una rápida movilización del alfa-tocoferol plasmático (AU)

Introduction: There is a controversy concerning to the modulation of hypoxia-induced oxidative stress; in addition, most studies covered mechanism of adaptation to altitude after an acclimation period, and they did not test the effects of acute exposures to hypoxia. Thus, the aim of the study was to establish oxidative status of trained swimmers analyzing the effects of exercise and acute exposure to moderate altitude. Materials and methods: Ten well-trained swimmers (5 females, 5 males) performed two similar mild-intensity training sessions of 90 minutes, one at an altitude of 630 m (normoxia) and the second of 2320 m (hypoxia). Training sessions were regulated to generate blood lactate values slightly higher than anaerobic threshold. 5 ml of blood samples were collected before and immediately after the exercise. Plasma were obtained by blood-centrifugation, samples were stored at -80ºC until analysis. Lipid peroxidation markers were hydroperoxides and thiobarbituric acid reactive substances (TBARS). Alpha-tocopherol was analyzed as non-enzymatic antioxidant mechanism. Comparisons between means were performed using one-way ANOVA. Results: Acute exposure to hypoxia produced a significant decrease of TBARS (20.78±8.36 nmol/ml, p<0.03) and, after effort, of hydroperoxides (20.78±8.36 nmol/ml, p<0.03) in men. In swimmers of both sexes, plasmatic alpha-tocopherol significantly decreased by hypoxia (men: 23.06±4.26 nmol/ml, women: 19.51±4.26 nmol/ml, p<0.001). In normoxia condition, women presented lower concentrations of TBARS (20.54±8.36 nmol/ml, p<0.03) and hydroperoxides (2.16±0.87 nmol/ml, p<0.03) than men. Mild-intensity training session did not modify oxidative stress in well-trained swimmers. Conclusions: In previous studies we demonstrated a non-enzymatic antioxidant mobilization from plasma to muscular and hepatic tissues as a response to an oxidative stress situation. Therefore, we conclude that acute exposure to moderate altitude could prevent oxidative stress in swimmers by a fast mobilization of plasmatic alpha-tocopherol (AU)

Pathophysiology of varicocele: evidence for oxidative stress as a mechanism pathway

There has never been an unswerving animal model for the study of varicocele; neither has a stable result been obtained. This has been as a result of personal interpretation of venous anatomical differences between human and rat models. Although the pathogenesis of varicocele remains uncertain, there is a growing body of data implicating hyperthermia, venous pressure, testicular blood flow, hormonal imbalance, toxic substances, and reactive oxygen species.The present study established the role of oxidative stress in the pathogenesis of varicocele using animal models. Four groups of rats were used, the first group served as the control, while the second, third and fourth groups of rats were varicocelized. The third and fourth group, in addition, had intraperitoneal and intramuscular treatment of 20 mg/kg and 25 mg/kg body weight of zinc chloride and alpha-tocopherol respectively. Fifty six days after, testicular weights and volumes, histology, morphometry, enzymatic and non-enzymatic antioxidants were evaluated.Result showed that the testes of varicocelized models treated with antioxidants had better oxidative status, geometric values and histological profiles compared to the untreated varicocelized models. These results indicated and validated the role of reactive oxygen in the pathogenesis of varicocele (AU)

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Protective effect of alpha tocopherol on contrast-induced nephropathy in rats

Background: Contrast-induced nephropathy (CIN) is a prominent cause of in-hospital acute kidney injury occurring after the administration of intravenous radiocontrast medium. Oxidative stress has been proposed as one of the more important mechanisms in the pathogenesis of CIN. The aim of the present study has been to determine the effect of alpha tocopherol on the reduction of renal damage in a rat model of CIN. Methods: Male Sprague Dawley rats were subjected into six groups pretreated with alpha-tocopherol (250 or 500mg/kg/day) or the vehicle tweeen 80 for 5 days before the induction of CIN. Renal function and oxidative stress markers; level of malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD) activity were determined. Kidney tissues were sectioned for pathohistological examination. Results: In the contrast media (CM) group, an increase in serum urea and creatinine was found. Tubular necrosis and peritubular capillary congestion were demonstrated in this group. Also, an imbalance of oxidative stress markers; an increase in MDA and a decreased SOD activity in kidney were shown. On the contrary, in CIN-induced rats administrated with alpha-tocopherol group, a significant reduction of renal function and renal MDA, together with a significant increase of renal SOD, were observed. Interestingly, a reduction in MDA and an increase of TAC in serum, along with prevention of tubular injury, were demonstrated in this group, as compared to the CM group. Conclusion: This present study demonstrated that alpha tocopherol showed protective effect on the rat renal damage induced CIN. Therefore, this vitamin could be used as an antioxidant to attenuate the radiocontrast oxidative damage (AU)

Antecedentes: La nefropatía inducida por contraste (NIC) constituye una causa importante del fracaso renal agudo en pacientes hospitalizados. Esta tiene lugar tras la administración de un medio de radiocontraste intravenoso. El estrés oxidativo se ha presentado como uno de los mecanismos más importantes de la patogénesis de la NIC. El objetivo de este estudio es determinar el efecto del alfa-tocoferol sobre la reducción del fracaso renal en un modelo de rata de NIC. Métodos: Las ratas Sprague Dawley machos, tratadas previamente con alfa-tocoferol (250 o 500 mg/kg/día) o con tween 80 durante los 5 días anteriores a la inducción de CIN, fueron divididas en 6 grupos. Se determinaron los marcadores de la función renal y del estrés oxidativo, el nivel de malondialdehído (MDA), la capacidad antioxidante total (CAT) y la actividad de la superóxido dismutasa (SOD). Se seccionaron los tejidos de los riñones para el examen histopatológico. Resultados: En el grupo de medio de contraste (MC), se detectó un aumento de la urea sérica y de la creatinina. Asimismo, se demostró la presencia de necrosis tubular y de congestión capilar peritubular en este grupo. También se detectó un desequilibrio de los marcadores de estrés oxidativo, un aumento de MDA y una disminución de la actividad de la SOD en el riñón. Por el contrario, en el grupo de ratas con NIC inducida a las que se les administró alfa-tocoferol, se observó una reducción importante de la función renal y de la MDA renal, junto con un aumento significativo de la SOD renal. Curiosamente, en comparación con el grupo MC, en este grupo se demostró una reducción de MDA y un aumento de la CAT sérica, así como la prevención de la lesión tubular. Conclusión: Este estudio ha demostrado que el alfa-tocoferol posee un efecto protector del daño renal en ratas con NIC inducida. Por lo tanto, esta vitamina podría utilizarse como antioxidante para atenuar el daño oxidativo del radiocontraste (AU)

Efecto de la suplementación de vitamina E en el rendimiento de una prueba incremental de consumo máximo de oxígeno en ratas wistar / Effect of vitamin E supplemantation on the performance of an incremental maximal oxigen uptake test in wistar rats

Diversas investigaciones han investigado el efecto de la suplementación de vitamina E en diversos marcadores de estrés oxidativo y en el rendimiento de diversas pruebas de resistencia, pero nunca en una prueba incremental hasta alcanzar el consumo de oxígeno máximo. Este trabajo pretende investigar el efecto de la toma de vitamina E en el rendimiento de una prueba incremental hasta alcanzar el consumo de oxígeno máximo en ratas. Se analizaron 2 grupos de ratas (G1: 190.8±1.83 gr; G2:198.0±0.86 gr), ambos realizaron una prueba incremental máxima en tapiz rodante (5’ a 25 cm/s mas aumentos de 3cm/s cada minuto hasta la extenuación). Dos horas antes de la prueba se administró al G1 un placebo (agua bidestilada) y alG2 una dosis de 1000UI/kg de peso de vitamina E, mediante una cánula endotraqueal. El G2 presentó unos valores deVO2max, VCO2max, VCO2relativo y RQ significativamente superiores (p<0.05) a los del G1. No se observaron diferencias significativas en las variables de VO2 relativo (G1: 87.1±7.61 vsG2: 91.0±3.55 ml/kg/min), tiempo final (G1: 1231.4±297.6 s vs G2: 1268.1±115.5 s) y velocidad final (G1: 76.6±14.91 cm/s vs G2: 78.3±5.89 cm/s). Estos datos muestran que la suplementación con una dosis de 1000 UI/kg peso de vitamina E no aumenta el rendimiento de ratas wistar al realizar una prueba incremental máxima hasta alcanzar el consumo de oxígeno máximo en tapiz rodante (AU)

Several studies have investigated the effect of vitamin E supplementation in various markers of oxidative stress and performance in different endurance exercises, but never in an incremental test to reach the maximum oxygen uptake. This work aims to investigate the effect of vitamin E supplementation on the performance of an incremental test to reach the maximum oxygen uptake in wistar rats. We analyzed two groups of wistar rats (G1: 190.8 g SEM 13.4, G2: 198.0 1.49 g SEM), both performed a maximum incremental test on a treadmill (5 ‘ to 25 cm/ s and increases of 3 cm/s every minute until exhaustion). Two hours before maximum incremental test G1 was administered a placebo (bi distilled water) and G2 was administered a dose of 1000UI/kg weight of vitamin E using an endotracheal tube.VO2max, VCO2max, relative VCO2 and RQ were significantly higher (p <0.05) in G2 when compared to G1. No significant differences were found for relative VO2 (G1: 87.14±7.61 vs G2: 91.00±3.55 ml/kg/min), final time (G1: 1231.40±297.63s vs G2: 1268.10±115.47 s) and final speed (G1: 76.60±14.91cm/s vs G2: 78.30±5.89 cm/s) between the two experimental groups. These data show that supplementation with a dose of1000 IU / kg vitamin E does not increase the performance of Wistar rats in an incremental test to reach maximum oxygen uptake (AU)

Retinol, β-carotene, α-tocopherol and vitamin D status in Europeanadolescents; regional differences an variability: A review / Estado de retinol, β-caroteno, α-tocopherol y vitamina D en adolescentes europeos; diferencias regionales y variabilidad: revisión

Currently, blood levels to define vitamin deficiency or optimal status in adolescents are extrapolated from adults. This may be not adequate as vitamin requirements during adolescence depend on the process of sexual maturation, rapid increasing height and weight, among other factors. In order to establish the state of the art, Medline database (www.ncvi.nlm.nih.gov) was searched for studies published in Europe between 1981 and 2010related to liposoluble vitamin status in adolescents. A comparison of the vitamin status published in there viewed articles was difficult due to the lack of studies, lack of consensus on cut-off levels indicating deficiency and optimal vitamin levels and the different age-ranges used. In spite of that, deficiency prevalence varied for vitamin D (13-72%), vitamin A (3%), E (25%) and β-carotene (14-19%). Additional factors were considered as possible determinants. We conclude that it is necessary to establish a consensus on acceptable ranges and cut-offs of these vitamins during adolescence. Representative data are still missing; therefore, there is a high need to get deeper into the investigation on liposoluble vitamins in this population group (AU)

En la actualidad, los diferentes valores sanguíneos que definen un estado óptimo o deficiente de vitaminas liposolubles en los adolescentes son extrapolados de los adultos. Sin embargo, podría no ser lo adecuado debido a que los requerimientos vitamínicos de los adolescentes están marcados por el proceso de maduración sexual y crecimiento entre otros factores. Para establecer el punto de partida, la base de datos Medline (www.ncvi.nlm.nih.gov) ha sido el medio utilizado para la búsqueda de los estudios publicados sobre el estado en vitaminas liposolubles en adolescentes europeos entre los años 1981 y 2010. Compararlos diferentes resultados obtenidos en los diferentes estudios fue difícil debido a la carencia de estudios, a la falta de consenso en los puntos de corte que indican deficiencia y estado óptimo y a los diferentes rangos de edad utilizados. A pesar de esto, en función de los estudios, se observa una variabilidad en la prevalencia de deficiencia de vitamina D (13-72%), vitamina A (3%), E (25%) y β-caroteno (14-19%). Otros factores adicionales fueron considerados como posibles determinantes del estado vitamínico. Se identifica la necesidad de establecer un consenso sobre los rangos aceptables y puntos de corte de estas vitaminas para este grupo de población y profundizar en la investigación de las vitaminas liposolubles en el periodo de la adolescencia (AU)

Cerebellar reduction in rats by gammairradiationis mitigated by pretreatment with methanolic extract of Vernonia amygdalina and alpha-tocopherol

This study evaluated the radioprotective effect of a methanolic extract of Vernonia amygdalina (MEVA), as compared with alpha-tocopherol (TOCO), on the effect of gamma-irradiation on the histomorphometry of the cerebellum of rats. Rats were administered with MEVA at 250, and 500 mg/kg/day, and TOCO at 500 mg/kg/day for 14 days, gamma-irradiated with 2.0 Gy on 15th day, and euthanized on the 16th day. Rat cerebella were processed for 5-6 µm paraffin-embedded sections and stained with Haematoxylin and Eosin and evaluated under the light microscope. The dimensions of the (i) the molecular layer (ML), (ii) the Purkinje layer (PL), (iii) the granular layer (GL), (iv) the density of Purkinje cell (DPc), and (v) the widest diameter of Purkinje cells (WDPc), were obtained using a microscope with a graticule. Data were analyzed using ANOVA. Gamma radiation caused a statistically significant reduction in the means of the PL (p<0.05), ML, GL, WDPc (p<0.01), and the DPc (p<0.001). Pretreatment with both 250 and 500 mg/kg doses of MEVA elicited a significant elevation of the means of these parameters when compared with the irradiation only groups as follows: PL (p<0.05), ML, GL, WDPc (p<0.01), and DPc (p<0.001). Similarly, pretreatment with TOCO elicited a significant elevation of the means of the same parameters thus: ML and GL (p<0.01), DPc and WDPc (p<0.001). Relatively, the 500 mg/kg dose of MEVA was more potent than the 250 mg/kg dose, and TOCO pretreatment was more potent than MEVA. The study demonstrates that pretreatment with MEVA and TOCO before exposure to 2 Gy of gamma rays significantly improves the radiation-induced changes in the cerebellum of Wistar rats (AU)

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Concentraciones de colesterol, alfa-tocoferol y retinoiodes en aceite de silicona tras su utilización como sustitutivo vítreo / Cholesterol, alpha-tocopherol, and retinoid concentrations in silicone oil used as a vitreous substitute

Objetivo: Determinar si existen concentraciones de compuestos lipofílicos de origen orgánico en muestras de aceite de silicona extraídas de ojos humanos y comprobar si existe alguna relación con el tiempo de permanencia intraocular del aceite.Métodos: Por cromatografía líquida de alta resolución (HPLC) se han determinado las concentraciones de ácido retinoico, retinol, retinal, colesterol y a-tocoferol en 23 muestras de aceite de silicona de 1.000 cs, extraídas de pacientes con desprendimientos complejos de retina con tiempos de permanencia intraocular variables (3 a 50 meses).Resultados: Se han encontrado concentraciones de todos los compuestos, sobre todo de colesterol, y en menor medida de alfa-tocoferol. Se ha observado una correlación inversa de la edad y las concentraciones de ácido retinoico (p=0,023). Y una correlación directa entre el tiempo de permanencia intraocular del aceite y los niveles de colesterol (p=0,0008) que se mantiene hasta los 20 meses.Conclusiones: Se confirma que el aceite de silicona no es una sustancia tan inerte ya que es capaz de disolver compuestos lipídicos procedentes de tejidos intraoculares. Existe una elevación linear de los niveles de colesterol que podría utilizarse como orientación para decidir cuándo extraer el aceite de silicona, aunque hacen falta estudios con series más grandes

Objective: To verify the existence of organic lipophylic compounds in silicone oil extracted from human eyes following its use for previous retinal detachment, and to determine the intraocular permanence time of these substances in the oil.Methods: Concentrations of retinoic acid, retinol, retinal, cholesterol and alpha-tocopherol were detected by HPLC in 23 samples of silicone oil extracted from patients with complicated retinal detachments. The time interval between the time of injection of the silicone oil and the subsequent assessment varied from 3 to 50 months (the permanence time).Results: All tested compounds were found in the samples, but these were most commonly cholesterol and less frequently alpha-tocopherol. There was an inverse relationship between retinoic acid concentration and age (p=0.023), and a direct relationship between cholesterol concentration and permanence time (p=0.0008) at least up to 20 months.Conclusions: These findings confirm that silicone oil is not an inert substance but is capable of extracting lipophylic compounds from the intraocular tissues. There is a clear linear elevation of cholesterol levels with increased intraocular permanence time. This finding could be used to further establish a safe permanence time for intraocular silicone oil used in ophthalmologic surgery. More studies with larger samples are warranted to evaluate this further

Evaluación del estado nutricional de vitamina E y lípidos en escolares cubanos de 6 a 11 años / Vitamin E and lipid nutritional status assessment in 6-11 year old Cuban school children

Fundamentos: En Cuba las primeras causas de muerteen la población están encabezadas por las enfermedadesdel corazón. Se considera que diversos factores ya en laniñez y la adolescencia podrían estar relacionados con eldesarrollo de estas enfermedades. El objetivo de este trabajofue analizar las concentraciones de α tocoferol ylípidos séricos así como los factores que las afectan y lasfuentes alimentarias de grasa y vitamina E en escolarescubanos.Métodos: El estudio se realizó en el primer semestre de2003 en una muestra de 1225 escolares de primero asexto grado de 7 provincias (edades de 6 a 11 años)para la determinación de vitamina A. De esta muestrainicial se tomó una submuestra de 710 escolares para ladeterminación de α tocoferol (αTF), colesterol (CT),triglicéridos (TG), HDL-colesterol (HDL-C), lípidos totalesy cálculo de αTF con las fracciones de lípidos. Losniveles plasmáticos de αTF se midieron por el método deHPLC y para el lipidograma se utilizaron técnicascolorimétricas. Se realizó una encuesta dietética dondese recogió la frecuencia de consumo en los seis mesesanteriores a la toma de la muestra de los 8 alimentosprincipales fuentes de grasas.Resultados: La media de los valores de αTF se encuentradentro de valores deficientes. El 55,6% de los escolaresde la zona occidental y el 42% de los de la zona centraltienen valores deficientes. El resultado del lipidogramaindica valores superiores de TG y HDL-C en la regióncentral con diferencias estadísticamente significativas. Lasvariables que explican los resultados de αTF son lasmayores concentraciones de CT y la región de procedencia;los escolares que viven en la región central tienenmayores concentraciones de αTF con respecto a los queviven en la región occidental. La ingestión de hidratos decarbono es superior al 70% de la ingestión calórica totaly la de grasa inferior al 20%.Conclusión: Diversos estudios sugieren que los predictoresbioquímicos de ateroesclerosis, como son las bajas concentracionesde HDL-C, pueden ser ya en la infancia tempranay la niñez muy buenos predictores de valores futuros,y el αTF es un factor adicional al que debe prestárseleuna atención especial en la nutrición en la infancia

Background: The main cause of mortality in Cuba is heartdisease. Several factors in childhood and adolescenceare considered as potentially influence the developmentof these diseases in adult life. The aim of this paper is toanalyze serum levels of α tocoferol and lipids as well asfactors influencing those and main food sources of fatand vitamin E in Cuban schoolchildren.Methods: The study was conducted in the first semestreof 2003 on a sample of 1225 schoolchidren attendingfirst to sixth grade in 7 provinces (age range 6 to 11years) for vitamin A assessment. In a subsample of 710schoolchildren from the initial sample serum levels of αtocoferol (αTF), cholesterol (CT), triglicerides (TG), HDLcholesterol(HDL-C), total lipids and computed ratios ofαTF and lipid fractions were assessed. Plasma levels ofαTF were determined by HPLC. Lipidogram was assessedby colorimetric techniques. Dietary intake was assessedby means of a food frequency questionnaire including the8 food items which are the main sources of fat in the dietfor the six month period prior to blood sample extraction.Results: Mean of αTF levels is in the range of defficientvalues. In the western region, 55,6% of the children haddefficient αTF levels and 42% in the central region. Resultsof lipidogram showed significant higher levels of TG andHDL-C in the central region. Variables explaining resultsof αTF levels were higher concentrations of CT and theregion of procedence. School children living in the centralregion had higher levels of αTF compared to those livingin the western region. Carbohydrate intake was above70% of total energy intake and fat intake was below 20%.Conclusion: Several studies suggest that biochemicalpredictors of atheroclerosis such as low HDL-c levels,can be in early childhood good predictors of future levels.αTF is an additional factor which should be considered inchildren nutrition

Distribución de la concentración sérica de -caroteno, retinol y -tocoferol en una muestra representativa de la población adulta de cataluña / Distribution of the serum concentration of -carotene, retinol and -tocopherol in a representative sample of the adult population of Catalonia (Spain)

FUNDAMENTO: Ciertas vitaminas ( -caroteno, retinol, -tocoferol) se han utilizado en la prevención de enfermedades neurovegetativas, inmunodeficiencias y cánceres por su posible relación con su etiopatogenia. Sin embargo, no se han descrito los valores séricos de dichos micronutrientes en la población. El objetivo de este estudio es describir la concentración sérica de caroteno, retinol, y -tocoferol en la población catalana y determinar la prevalencia de déficit nutricional de estos micronutrientes. MÉTODO: Se obtuvo una submuestra de la muestra representativa de 18-75 años de edad que participó en el Estudio del Estado Nutricional de la Población Catalana (1992-1993). Se determinó la concentración sérica de -caroteno, retinol y -tocoferol. RESULTADOS: La concentración sérica de -caroteno fue de 0,39 y 0,49 µmol/l en varones y mujeres, respectivamente, y la prevalencia de déficit fue del 62 por ciento en los varones y del 54 por ciento en las mujeres. La concentración sérica de retinol fue superior en varones (1,98 µmol/l) que en mujeres (1,68 µmol/l) y no se detectó déficit para esta vitamina. En las mujeres de 18 a 34 años de edad, un 12 por ciento presenta un déficit marginal de -tocoferol. CONCLUSIONES: Se observa un buen estado nutricional de retinol y -tocoferol en la población estudiada. Sin embargo, destaca la elevada prevalencia de valores subóptimos de -caroteno en la población, los cuales deberían corregirse aumentando el consumo de frutas y verduras (AU)

Evaluación histopatológica de la acción de derivados de la vitamina e en el proceso cicatricial de un modelo de cirugía filtrante / Histopathological evaluation of vitamin e in surgical fistula closure

Objetivo: Describir el efecto de los derivados del a-tocoferol (acetato y succinato ácido) sobre las características histopatológicas de la fístula quirúrgica en un modelo experimental de cirugía filtrante. Material y métodos: 30 conejos pigmentados fueron divididos en 3 grupos de estudio. Veinticuatro horas antes de la cirugía se inyectaron subconjuntivalmente 0,5 ml de solución según el grupo de tratamiento: grupo I (n=10) solución salina balanceada (BSS) en etanol al 0,75 por ciento, grupo II (n=10) 100 µgrs de acetato de alfa-tocoferol (AT) en BSS con etanol al 0,75 por ciento, y grupo III (n=10) 100 µgrs de succinato ácido de alfa-tocoferol (ST) en BSS con etanol al 0,75 por ciento. Se evaluaron los hallazgos histológicos 30 días después de la cirugía. Resultados: Los grupos tratados con derivados del alfa-tocoferol mostraron mayor porcentaje de fístulas permeables y áreas cicatriciales de menor extensión. Existió un infiltrado celular subconjuntival de células mononucleares y eosinófilos. Conclusiones: El empleo de derivados del alfa-tocoferol en cirugía filtrante experimental mejora los parámetros histológicos de inhibición de los procesos de cicatrización vinculados al fracaso de la cirugía filtrante (AU)

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