Etudes Perte de poids

Les boosters de NO pour maigrir sur le long terme?

14/12/2017 | Etudes Perte de poids et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

Ca fait quand même un peu beaucoup…

Sildenafil induces browning of subcutaneous white adipose tissue in overweight adults
Metabolism Volume 78, January 2018, Pages 106-117

To investigate that short-term treatment of sildenafil can induce browning of subcutaneous white adipose tissue (sWAT) in human adults.

Design
A randomized, double-blinded, placebo-controlled, parallel group trial.

Methods
Sixteen eligibility overweight male subjects were recruited, comparing 100 mg/day sildenafil versus an identical placebo therapy for 7 days. sWAT samples were collected from subjects before and after 7-day sildenafil or placebo interventions.

Results
The results showed that multilocular UCP1-positive adipocytes existed in sWAT samples from subjects after sildenafil treatment. Compared to before treatment in both group as well as after treatment in placebo, sildenafil significantly decreased adipocyte size, increased the expressions of UCP1 protein and mRNA, mitochondrial density, and leak respiratory capacity in sWAT (p < 0.05). Sildenafil also increased plasma cyclic guanosine-3′,5′-monophosphate (cGMP) and catecholamine concentrations (p < 0.05), and consequently activated the expressions of vasodilator-stimulated phosphoprotein (VASP) and p70 ribosomal S6 kinase 1 (S6 K1) (p < 0.05). Sildenafil did not activate typical brown fat.

Conclusions
The current findings demonstrate that sildenafil can induce browning of sWAT in human, and this action may be through cGMP-dependent protein kinase I and mechanistic/mammalian target of rapamycin (mTOR) signaling pathways. Sldenafil may be a promising treatment for metabolic disease.

Les protéines laitières rapides ont un impact à court et à long terme sur la glycémie

05/11/2017 | Etudes sur les hormones et Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge

 

Cela explique que l’on peut ne pas le sentir au début puis y devenir sensible

Comparison between pre–exercise casein peptide and intact casein supplementation on glucose tolerance in high–fat diet–fed mice

Yutaka Matsunaga         Applied Physiology, Nutrition, and Metabolism, 2017

We hypothesized that along with exercise, casein peptide supplementation would have a higher impact on improving glucose tolerance than intact casein. Male six–week–old ICR mice were provided a high–fat diet to induce obesity and glucose intolerance. The mice were randomly divided into four treatment groups: control (Con), endurance training (Tr), endurance training with intact casein supplementation (Cas+Tr), and endurance training with casein peptide supplementation (CP+Tr). The mice in each group were orally administrated water, intact casein, or casein peptide (1.0 mg/g BW, everyday), and then subjected to endurance training (15–25 m/min, 60 min, 5 times/week for 4 weeks) on a motor–driven treadmill 30 min after ingestion. Our results revealed that total intra–abdominal fat was significantly lower in CP+Tr than in Con (p<0.05). Following an oral glucose tolerance test, the blood glucose area under the curve (AUC) was found to be significantly smaller for CP+Tr than for Con (p<0.05). Moreover, in the soleus muscle, GLUT4 protein levels were significantly higher in CP+Tr than in Con (p<0.01). However, intra–abdominal fat, blood glucose AUC, and GLUT4 protein content in the soleus muscle did not alter in Tr and Cas+Tr when compared with Con. These observations suggest that pre–exercise casein peptide supplementation has a higher effect on improving glucose tolerance than intact casein does in high–fat diet–fed mice.

Une supplémentation en corps cétoniques booste la récupération énergétique

17/08/2017 | Etudes cardio et Etudes Compléments alimentaires et Etudes Perte de poids

 

A Ketone Ester Drink Increases Postexercise Muscle Glycogen Synthesis in Humans
HOLDSWORTH, DAVID A         Medicine & Science in Sports & Exercise: September 2017 - Volume 49 - Issue 9 - p 1789–1795

Introduction: Physical endurance can be limited by muscle glycogen stores, in that glycogen depletion markedly reduces external work. During carbohydrate restriction, the liver synthesizes the ketone bodies, D-β-hydroxybutyrate, and acetoacetate from fatty acids. In animals and in the presence of glucose, D-β-hydroxybutyrate promotes insulin secretion and increases glycogen synthesis. Here we determined whether a dietary ketone ester, combined with plentiful glucose, can increase postexercise glycogen synthesis in human skeletal muscle.

Methods: After an interval-based glycogen depletion exercise protocol, 12 well-trained male athletes completed a randomized, three-arm, blinded crossover recovery study that consisted of consumption of either a taste-matched, zero-calorie control or a ketone monoester drink, followed by a 10-mM glucose clamp or saline infusion for 2 h. The three postexercise conditions were control drink then saline infusion, control drink then hyperglycemic clamp, or ketone ester drink then hyperglycemic clamp. Skeletal muscle glycogen content was determined in muscle biopsies of vastus lateralis taken before and after the 2-h clamps.

Results: The ketone ester drink increased blood D-β-hydroxybutyrate concentrations to a maximum of 5.3 versus 0.7 mM for the control drink (P < 0.0001). During the 2-h glucose clamps, insulin levels were twofold higher (31 vs 16 mU·L−1, P < 0.01) and glucose uptake 32% faster (1.66 vs 1.26 g·kg−1, P < 0.001). The ketone drink increased by 61 g, the total glucose infused for 2 h, from 197 to 258 g, and muscle glycogen was 50% higher (246 vs 164 mmol glycosyl units per kilogram dry weight, P < 0.05) than after the control drink.

Conclusion: In the presence of constant high glucose concentrations, a ketone ester drink increased endogenous insulin levels, glucose uptake, and muscle glycogen synthesis.

Rôle de l’entraînement sur la densité mitochondriale

09/06/2017 | Etudes cardio et Etudes Perte de poids

 

Exercise training increases skeletal muscle mitochondrial volume density by enlargement of existing mitochondria and not de novo biogenesis
Anne-Kristine Meinild Lundby       Acta physiol 2017

Aims

1) determine whether exercise induced increases in muscle mitochondrial volume density (MitoVD) is related to enlargement of existing mitochondria or de novo biogenesis, 2) establish if measures of mitochondrial-specific enzymatic activities are valid biomarkers for exercise induced increases in MitoVD.
Method

Skeletal muscle samples were collected from twenty-one healthy males prior to and following 6 weeks of endurance training. Transmission electron microscopy was used for estimation of mitochondrial densities and profiles. Biochemical assays, western blotting and high resolution respirometry were applied to detect changes in specific mitochondrial functions.
Result

MitoVD increased with 55 ± 9% (P

< 0.001), whereas the number of mitochondrial profiles per area of skeletal muscle remained unchanged following training

. Citrate synthase activity (CS) increased (44 ± 12%, P < 0.001) however, there were no functional changes in oxidative phosphorylation capacity (OXPHOS, CI+IIP) or cytochrome c oxidase (COX) activity. Correlations were found between MitoVD and CS (P=0.01; r=0.58), OXPHOS, CI+CIIP (P=0.01; R=0.58) and COX (P=0.02; R=0.52) before training, after training a correlation was found between MitoVD and CS activity only (P=0.04; R=0.49). Intrinsic respiratory capacities decreased (P < 0.05) with training when respiration was normalized to MitoVD. This was not the case when normalized to CS activity although the percentage change was comparable.
Conclusions

MitoVD was increased by inducing mitochondrial enlargement rather than de novo biogenesis. CS activity may be appropriate to track training induced changes in MitoVD.

Rôles des peptides mitochondriaux dans la perte de graisse

09/06/2017 | Etudes cardio et Etudes Perte de poids

 

Mitochondrial derived peptides as novel regulators of metabolism
Su-Jeong Kim             J Physiol 2017
         
Mitochondrial derived peptides represent a new class of circulating signalling molecules. Humanin, the first member of this class, has been shown to have several metabolic effects such as reducing weight gain and visceral fat and increasing glucose stimulated insulin release. The discovery of several other new members such as MOTS-c and SHLP1-6, have further added to this group. These new peptides have also been found to affect metabolism with MOTS-c potently decreasing weight gain in mice on a high fat diet. In this review, we will cover the basic biology of this class of peptides and discuss the relevance to organismal metabolism.

L’équilibre en sodium est plus compliqué qu’il n’y parait

09/05/2017 | Etudes sur les hormones et Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge

 

Increased salt consumption induces body water conservation and decreases fluid intake
Natalia Rakova       J Clin Invest April 17, 2017 - More info

The idea that increasing salt intake increases drinking and urine volume is widely accepted. We tested the hypothesis that an increase in salt intake of 6 g/d would change fluid balance in men living under ultra-long-term controlled conditions.

METHODS. Over the course of 2 separate space flight simulation studies of 105 and 205 days’ duration, we exposed 10 healthy men to 3 salt intake levels (12, 9, or 6 g/d). All other nutrients were maintained constant. We studied the effect of salt-driven changes in mineralocorticoid and glucocorticoid urinary excretion on day-to-day osmolyte and water balance.

RESULTS. A 6-g/d increase in salt intake increased urine osmolyte excretion, but reduced free-water clearance, indicating endogenous free water accrual by urine concentration. The resulting endogenous water surplus reduced fluid intake at the 12-g/d salt intake level. Across all 3 levels of salt intake, half-weekly and weekly rhythmical mineralocorticoid release promoted free water reabsorption via the renal concentration mechanism. Mineralocorticoid-coupled increases in free water reabsorption were counterbalanced by rhythmical glucocorticoid release, with excretion of endogenous osmolyte and water surplus by relative urine dilution. A 6-g/d increase in salt intake decreased the level of rhythmical mineralocorticoid release and elevated rhythmical glucocorticoid release. The projected effect of salt-driven hormone rhythm modulation corresponded well with the measured decrease in water intake and an increase in urine volume with surplus osmolyte excretion.

CONCLUSION. Humans regulate osmolyte and water balance by rhythmical mineralocorticoid and glucocorticoid release, endogenous accrual of surplus body water, and precise surplus excretion.

Vitamine P4 contre la fatigue

30/04/2017 | Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge

 

Short-term effects of troxerutin (vitamin P4) on muscle fatigue and gene expression of Bcl-2 and Bax in the hepatic tissue of rats

Mohammad Zamanian         Revue canadienne de physiologie et pharmacologie 2017

Dans les présents travaux, nous avons étudié l’effet de la troxérutine (TRX) sur la fatigue musculaire et l’expression des gènes Bcl-2 et Bax dans le tissu hépatique de rat. Nous avons réparti aléatoirement 40 rats Wistar mâles dans les quatre groupes suivants : témoin et administration de TRX à 75 (TRX75), 150 (TRX150) et 300 mg/kg par jour (TRX300). Les groupes TRX et placebo ont reçu pendant 7 jours de la TRX et de l’eau, respectivement. Le 7e jour, tous les animaux ont été euthanasiés immédiatement après un test de nage menant à l’épuisement, et nous avons mesuré plusieurs paramètres biochimiques liés à la fatigue et à l’expression des gènes Bcl-2 et Bax dans le tissu hépatique. Nos résultats ont montré que dans le groupe TRX300, le temps de nage écoulé avant l’épuisement était 1,2 fois plus élevé que dans le groupe témoin (résultats statistiquement significatifs : P < 0,001).

Dans le groupe TRX300, l’activité de l’ALT diminuait et l’activité hépatique de la SOD augmentait de façons nettement plus marquées que dans le groupe témoin (P < 0,05 et P < 0,01, respectivement). De plus, la TRX entraînait une diminution de l’expression de l’ARNm du gène Bax et une augmentation du rapport Bcl-2/Bax nettement plus marquées que dans le groupe témoin (P < 0,001 dans les deux cas).

D’après nos données, la TRX exerce une action anti-apoptotique et hépatoprotectrice à la suite d’un exercice de nage menant à l’épuisement.

Page 1 sur 51 pages  1 2 3 >  Last »