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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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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http://www.stripes.com/news/aafes-pulls-weight-loss-bodybuilding-supplement-from-shelves-1.162471

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Exploration détaillée des composantes de la glycorégulation chez des sportifs sujets aux hypoglycémies d’effort. Intérêt de l’oral minimal model
J.-F. Brun   Science & Sports Volume 26, Issue 5, November 2011, Pages 286-291

Les hypoglycémies à l’exercice (HE) sont une situation très fréquente mais peu étudiée. Elles surviennent chez des sujets présentant des valeurs élevées d’insulino-sensibilité (SI) et d’efficience glucidique (SG). SI et SG peuvent être calculées à partir de repas-tests par une modélisation mathématique qui permet aussi une étude approfondie des composantes de la sécrétion d’insuline.

Méthodes et résultats
Nous avons étudié les résultats fournis par cette méthode chez 19 sportifs se plaignant d’HE comparés à 58 sportifs appariés ne présentant pas ce problème. On observe des valeurs plus élevées de SI (p < 0,05) et SG (p

Conclusion
Ainsi, ces sujets ont une assimilation glucidique massive, leur sécrétion d’insuline se réduisant de façon compensatoire mais cette réduction a des limites et peut s’avérer insuffisante, notamment en ce qui concerne la sensibilité β-pancréatique au glucose.

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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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Anabolic effect of plant brassinosteroid
The FASEB Journal vol. 25 no. 10 3708-3719   Debora Esposito, Slavko Komarnytsky, Sue Shapses and Ilya Raskin

Brassinosteroids are plant-derived polyhydroxylated derivatives of 5a-cholestane, structurally similar to cholesterol-derived animal steroid hormones and insect ecdysteroids, with no known function in mammals. 28-Homobrassinolide (HB), a steroidal lactone with potent plant growth-promoting property, stimulated protein synthesis and inhibited protein degradation in L6 rat skeletal muscle cells (EC50 4 μM) mediated in part by PI3K/Akt signaling pathway. Oral administration of HB (20 or 60 mg/kg/d for 24 d) to healthy rats fed normal diet (protein content 23.9%) increased food intake, body weight gain, lean body mass, and gastrocnemius muscle mass as compared with vehicle-treated controls. The effect of HB administration increased slightly in animals fed a high-protein diet (protein content 39.4%). Both oral (up to 60 mg/kg) and subcutaneous (up to 4 mg/kg) administration of HB showed low androgenic activity when tested in the Hershberger assay. Moreover, HB showed no direct binding to the androgen receptor in vitro. HB treatment was also associated with an improved physical fitness of untrained healthy rats, as evident from a 6.7% increase in lower extremity strength, measured by grip test. In the gastrocnemius muscle of castrated animals, HB treatment significantly increased the number of type IIa and IIb fibers and the cross-sectional area of type I and type IIa fibers. These findings suggest that oral application of HB triggers selective anabolic response with minimal or no androgenic side-effects and begin to elucidate the putative cellular targets for plant brassinosteroids in mammals

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Palumbo précise qu’il a essayé toutes les chaines de fast food US et que seul McDo marche
http://www.rxmuscle.com/videos/lifestyle/4234-mcdonalds-restaurant-review-with-palumbo,-juan-morel,-akim-williams,-jtp,-mike-popkin.html

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