The effects of acute alcohol consumption on recovery from a simulated rugby match
Journal of Sports Sciences Volume 30, Issue 3, 2012

In this study, we investigated the effects of acute post-exercise alcohol consumption on measures of physical performance, creatine kinase, and immunoendocrine function in the 48 h following a rugby game simulation. Ten male senior rugby union players completed a rugby game simulation after which they consumed either 1 g of alcohol per kilogram of body mass or a non-alcoholic control beverage. Agility, 15 m sprint, countermovement jump, and srummaging performance were assessed pre-simulation and 24 and 48 h post-simulation. White blood cell count, testosterone, cortisol, and creatine kinase were measured before the simulation and 30 min, 12, 24, 36, and 48 h after the simulation. One week after the first trial, participants completed the second simulation after which the other beverage was consumed. The acute consumption of alcohol after a rugby game simulation negatively affected countermovement jump performance in the days following the simulation (P = 0.028). No differences between treatments were observed for the other criterion measures made in this study. In conclusion, after 80 min of a simulated rugby game, the consumption of 1 g of alcohol per kg body mass negatively impacts lower body vertical power output. However, performance of tasks requiring repeated maximal muscular effort is not affected.

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Effet de l’huile fixe de la nigelle (Nigella sativa L.) sur le profil des androgènes chez le rat male
  Phytothérapie Volume 9, Number 6, 338-342,
M. El Khasmi, A. Issaoub Allah, M. Farh, F. Riad, A. Safwate, N. El Abbadi and E. H. Tahri

Les extraits des graines de la nigelle sont largement utilisés dans la médecine traditionnelle. Nous avons étudié l’effet de l’huile fixe de la nigelle sur les taux plasmatiques de la testostérone (T), de l’hormone folliculostimulante (FSH), de l’hormone lutéinisante (LH) et sur le poids corporel et celui des organes reproducteurs chez le rat. Vingt rats mâles ont été divisés en deux groupes de dix: le groupe témoin et celui traité avec l’huile de la nigelle (0,5 ml/kg) par voie intrapéritonéale pendant 30 jours. Nos résultats ont montré que l’huile de la nigelle augmente significativement la masse des organes reproducteurs et les concentrations plasmatiques de la T, de la FSH et de la LH comparativement aux animaux témoins (p < 0,05). L’induction de la stéroïdogenèse observée pourrait être médiée par une activation de l’axe hypothalamohypophysogonadique.

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Pycnogeno supplementation improves cognitive function, attention and mental performance in students
Panminerva Med, 2011 Sept; 53(3 Suppl 1): 75-82.

In a study involving 53 healthy university students between the ages of 18 and 27 years, supplementation with French maritime pine bark extract (Pycnogenol(R)) for a period of 8 weeks was found to be associated with statistically significant improvements in cognitive function, specifically, improved sustained attention, memory, executive functions and mood ratings, as compared to controls who were not given Pycnogenol(R). The students were given university examinations, and results found that in those given Pycnogenol(R), students failed 7 tests out of 112 (6.25%), as compared to controls who failed 9 tests out of 84 (10.71%), and the average test score among those given Pycnogenol(R) was 26.1 as compared to 23.81 in controls. The authors conclude, “This study indicates a role for Pycnogenol to improve cognitive function in normal students.”

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Association between plasma 25-OH vitamin D and testosterone levels in men
Katharina Nimptsch                 Clinical Endocrinology

Objective:  A small randomized controlled trial suggested that vitamin D might increase the production of testosterone in men, which is supported by experimental studies in animals and a cross-sectional study showing positive associations between plasma 25-hydroxyvitamin D [25(OH)D] and testosterone and concordant seasonal variation of both biomarkers.

Design and Measurements:  We investigated the cross-sectional association of plasma 25(OH)D levels and total and free testosterone measured by immunoassay in 1,362 male participants of the Health Professionals Follow-up Study who were selected for a nested case-control study on prostate cancer using multivariate adjusted linear and restricted cubic spline regression models.

Results:  25(OH)D was positively associated with total and free testosterone levels. From the lowest to the highest 25(OH)D quintile, multivariate adjusted means (95% confidence interval) were 18.5 (17.7; 19.4), 19.4 (18.6; 20.2), 19.6 (18.8; 20.4), 20.1 (19.3; 20.9) and 20.0 (19.1; 20.8); p-trend=0.003) for total testosterone and 97.7 (93.9; 101.5), 98.2 (94.1; 102.2), 99.2 (95.2; 103.2), 100.7 (96.9; 104.5) and 101.5 (97.6; 105.4; p-trend=0.03) for free testosterone. The shapes of the dose-response curves indicate that the association between 25(OH)D and total and free testosterone is linear at lower levels of 25(OH)D (below approximately 75-85 nmol/l), reaching a plateau at higher levels. Unlike for 25(OH)D, we did not observe any seasonal variation of testosterone concentrations.

Conclusion:  This study supports previously reported positive associations between vitamin D and testosterone although we did not observe parallel seasonal variation patterns. Possible causality and direction of the vitamin D-testosterone association deserve further scientific investigation.

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L’athlète master d’endurance, un modèle de vieillissement réussi
Science & Sports 2012 Louis J

Objectifs
Cet article vise à présenter l’athlète master d’endurance à travers ses caractéristiques physiologiques et passe en revue l’effet de l’âge sur les principaux facteurs de la performance en endurance.

Actualités
Le déclin de la performance physique est inévitable avec l’avancée dans l’âge. Néanmoins, certaines personnes âgées continuent à s’entraîner autant que leurs homologues plus jeunes afin de repousser les effets du vieillissement. Ces « athlètes masters » présentent très peu d’altérations physiques, sont capables de performances remarquables dans les épreuves d’endurance et constituent ainsi de véritables modèles de vieillissement réussi. L’activité physique régulière leur permet de limiter l’altération des capacités physiologiques nécessaires à une bonne qualité de vie.

Perspectives
L’athlète master constitue un modèle expérimental intéressant dans l’étude du vieillissement, sans les effets confondus d’un mode de vie sédentaire et du déconditionnement qui accentuent le processus de vieillissement. Les recherches futures devraient ainsi inclure les athlètes masters afin d’enrichir les connaissances sur le processus de vieillissement et sur les stratégies bénéfiques pour bien vieillir.

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Melatonin: The smart killer: The human trophoblast as a model
Dave Lanoix         Molecular and Cellular Endocrinology Volume 348, Issue 1, 2 January 2012, Pages 1-11

Melatonin has both the ability to induce intrinsic apoptosis in tumor cells while it inhibits it in non-tumor cells. Melatonin kills tumor cells through induction of reactive oxygen species generation and activation of pro-apoptotic pathways. In contrast, melatonin promotes the survival of non-tumor cells due to its antioxidant properties and the inhibition of pro-apoptotic pathways. In primary human villous trophoblast, a known pseudo-tumorigenic tissue, melatonin promotes the survival through inhibition of the Bax/Bcl-2 pathway while in BeWo choriocarcinoma cell line melatonin induces permeabilization of the mitochondrial membrane leading to cellular death. These findings suggest that the trophoblast is a good model to study the differential effects of melatonin on the intrinsic apoptosis pathway. This review describes the differential effects of melatonin on the intrinsic apoptosis pathway in tumor and non-tumor cells and presents the trophoblast as a novel model system in which to study these effects of melatonin.

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Cortisol acutely reduces selective attention for erotic words in healthy young men
Psychoneuroendocrinology Volume 36, Issue 9, October 2011, Pages 1407-1417   Peter Putman, Sylvia Berling

Psychological stress prompts activity of the hypothalamic–pituitary–adrenal (HPA) axis resulting in increased release of cortisol. Long-term HPA aberrations have been observed for stress-related affective disorders but research into acute effects of cortisol on affect-regulation has only recently begun. Previous studies reported that exogenous cortisol acutely attenuated automatic attentional processing of task-irrelevant threatening information. This has been taken to suggest that cortisol may have acute anxiolytic properties, possibly through facilitating inhibition of threatening information. However, the role of cortisol in attentional inhibition of non-threatening arousing stimuli remained unclear. Therefore acute effects of 40 mg cortisol on performance of a masked and unmasked emotional Stroop task (EST) were assessed. Results for only the unmasked task demonstrated EST interference (interpreted as increased automatic attention) for erotic stimuli which was abolished by cortisol administration. This implies that effects of cortisol may not be restricted to attenuation of specifically anxiogenic information processing, as previously suggested.

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