Cliquez sur les images pour acquérir mes livres : frais de port gratuits et envoi rapide.

Pour suivre mon actualité ou me contacter : sur Facebook.

Effet anabolique de l’acide hyaluronique et de l’extrait de cartilage

26/03/2015 | Etudes Compléments alimentaires et Etudes Anti-âge

 

Novel Natural Compounds with Potential to Prevent and Treat Skeletal Muscle Atrophy
A Torrent         April 2015   The FASEB Journal vol. 29 no. 1 Supplement 737.4      

Objective: Chronic muscle inactivity and mechanical unloading (e.g. bed rest and cast immobilization) result in skeletal wasting and weakness. Muscle weakness is also an early and frequent finding in knee Osteoarthritis (OA) and is a risk factor of OA onset. There is a profound need to develop novel therapeutic strategies because current treatments are ineffective. The aim of this study was to investigate the therapeutic potential of two natural substances to combat muscle atrophy: an extract from rooster comb, IB0004 that contains mainly hyaluronic acid; and BIX003, another extract from porcine cartilage, rich in bioactive substances.

Methods: An assay was performed to evaluate the potential to stimulate proliferation of murine C2C12 muscle cells. In another experiment, we evaluated whether IB0004 or BIX003 could prevent muscle atrophy (i.e. myotube thickness).

Results: IB0004 and BIX003 exerted little effect on cell proliferation in 10% FBS growth serum, but they significantly stimulated proliferation in low-serum media after 48 hours treatment (131% and 48% increase, respectively). In addition, treatments with either extract were able to counteract myotube atrophy when compared with the 0% control, as evident from prevention of the 20% reduction in myotube width.

Conclusion: These data indicate that BIX003 and IB0004 have potential anabolic effects on muscle that could counteract cell atrophy under adverse conditions. Both preparations may have therapeutic potential for preventing atrophy in muscle wasting conditions such as disuse atrophy, sarcopenia, and other disorders. Further studies in animal models should be performed to confirm these results.

Toxicité d’extraits de baguettes, de cure-dents et de verres de carton jetables

24/03/2015 | Etudes Anti-âge

 

Super

Toxicity of extracts from disposable chopsticks, toothpicks, and paper cups on L-929 cells

Juntao Li   Revue canadienne de physiologie et pharmacologie, 2015, 93(4): 223-226

Évaluer la toxicité d’extraits de baguettes, de cure-dents et de verres de carton jetables sur les cellules L-929. Méthode : Les extraits de baguettes, de cure-dents et de verres de carton jetables ont été utilisés pour préparer le milieu de culture cellulaire selon les standards nationaux, et la morphologie des cellules L-929 a été observée en microscopie optique. Le taux de perte de cellules adhérentes a été évalué par coloration d’exclusion au bleu de trypan et la prolifération cellulaire a été déterminée par un dosage WST-1.

Résultats : Comparativement au groupe contrôle, les cellules cultivées dans le milieu contenant les extraits présentaient des signes d’apoptose et de nécrose après une culture de 4 ou 7 jours, et le taux de perte de cellules adhérentes était significativement accru (P < 0,05). Une diminution évidente de la viabilité cellulaire était aussi observée (P < 0,05).

Conclusion : Les extraits de baguettes, de cure-dents et de verres de carton jetables peuvent affecter la croissance et la prolifération des cellules L-929 et sont potentiellement néfastes pour la santé humaine.

Comment diminuer de 50% l’apport calorique de son riz?

24/03/2015 | Etudes Perte de poids

 

Mettre 1 cuillère d’huile de noix de coco dans l’eau de cuisson. Faire cuire le riz dans l’eau bouillante 20 min et mettre au frigo 12 h. La proportion de glucides que l’on ne peut pas digérer aura été multipliée par 10.


Rice (Oryza sativa L.) resistant starch and novel processing methods to increase resistant starch concentration
249th National Meeting & Exposition of the American Chemical Society (ACS). Sudhair JA

Obesity is an emerging health crisis in many developing countries. To find food based solutions for obesity, rice resistant starch (RS) concentrations and novel ways to increase RS concentrations were studied. A total of 38 Sri Lankan rice varieties were tested; the RS concentrations ranged from 0.30 to 4.65%. The traditional rice varieties had significantly higher RS concentrations than old and improved varieties. Bg 305 had the least RS concentration out of all. However, applying different heating and cooling conditions with pure coconut oil showed RS concentrations increased by at least 10 times. The increase in RS content could be attributed to the increase in RS3 and RS5 types, suggesting potential to increase these types of RS in rice. This study results clearly show that rice, when cooked properly, could be a good low calorie food source for obesity reduction. In-vivo glycemic effects of RS studies are in progress.

Pour rappel:

L’amidon résistant se présente sous quatre types :

AR 1 : c’est un amidon physiquement inaccessible, présent par exemple dans les graines ou les légumineuses, ou bien dans les grains entiers (non broyés).
AR 2 ; c’est un amidon présent naturellement sous forme de grains d’amidon, par exemple dans les pommes de terre crues, les bananes vertes, ou les maïs à forte teneur en amylose.
AR 3: c’est un amidon résistant qui se forme par rétrogradation de l’amylose lorsque des aliments riches en amidon sont cuits puis refroidis, par exemple le pain, les flocons de maïs ou les pommes de terre en salade.
AR 4 : il s’agit d’amidon chimiquement modifiés pour résister aux enzymes digestifs. Ce type d’amidon présente une grande variété de structures inconnues à l’état naturel.

 

L’alimentation pour vivre longtemps ou pour avoir les couilles pleines, il faut choisir!

18/03/2015 | Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

Macronutrient balance, reproductive function, and lifespan in aging mice
Samantha M. Solon-Biet           PNAS 2015   March 17, 2015 vol. 112 no. 11

A fundamental tenet of life-history theory is that reproduction and longevity trade off against one another. Experiments on invertebrates show that, rather than competing for limiting resources, reproduction and lifespan are optimized on different dietary macronutrient compositions. In mice, studies have yet to establish the relationship between macronutrient balance, reproduction, and lifespan. We evaluated the effects of macronutrients and energy on lifespan and reproductive function. Indicators of reproductive function (uterine mass, ovarian follicle number, testes mass, epididymal sperm counts) were optimized by high protein (P), low carbohydrate (C) diets whereas lifespan was greatest on low P:C diets. Corpora lutea and estrous cycling were higher in females on lower P:C diets. Macronutrient balance has profound and opposing effects on reproduction and longevity.

Abstract
In invertebrates, reproductive output and lifespan are profoundly impacted by dietary macronutrient balance, with these traits achieving their maxima on different diet compositions, giving the appearance of a resource-based tradeoff between reproduction and longevity. For the first time in a mammal, to our knowledge, we evaluate the effects of dietary protein (P), carbohydrate (C), fat (F), and energy (E) on lifespan and reproductive function in aging male and female mice. We show that, as in invertebrates, the balance of macronutrients has marked and largely opposing effects on reproductive and longevity outcomes. Mice were provided ad libitum access to one of 25 diets differing in P, C, F, and E content, with reproductive outcomes assessed at 15 months. An optimal balance of macronutrients exists for reproductive function, which, for most measures, differs from the diets that optimize lifespan, and this response differs with sex. Maximal longevity was achieved on diets containing a P:C ratio of 1:13 in males and 1:11 for females. Diets that optimized testes mass and epididymal sperm counts (indicators of gamete production) contained a higher P:C ratio (1:1) than those that maximized lifespan. In females, uterine mass (an indicator of estrogenic activity) was also greatest on high P:C diets (1:1) whereas ovarian follicle number was greatest on P:C 3:1 associated with high-F intakes. By contrast, estrous cycling was more likely in mice on lower P:C (1:8), and the number of corpora lutea, indicative of recent ovulations, was greatest on P:C similar to those supporting greatest longevity (1:11).

Variations des réserves de glycogène sur 24h

13/03/2015 | Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge

 

Diurnal variation in skeletal muscle and liver glycogen in humans with normal health and Type 2 diabetes
Clinical Science (2015) 128, (707–713)      Mavin Macauley

Storage of food-derived glucose as muscle and liver glycogen is vital to avoid damaging swings plasma osmolarity. We report that in Type 2 diabetes, muscle glycogen storage was completely inactive although liver glycogen storage was normal.

In health, food carbohydrate is stored as glycogen in muscle and liver, preventing a deleterious rise in osmotically active plasma glucose after eating. Glycogen concentrations increase sequentially after each meal to peak in the evening, and fall to fasting levels thereafter. Skeletal muscle accounts for the larger part of this diurnal buffering capacity with liver also contributing. The effectiveness of this diurnal mechanism has not been previously studied in Type 2 diabetes. We have quantified the changes in muscle and liver glycogen concentration with 13C magnetic resonance spectroscopy at 3.0 T before and after three meals consumed at 4 h intervals. We studied 40 (25 males; 15 females) well-controlled Type 2 diabetes subjects on metformin only (HbA1c (glycated haemoglobin) 6.4±0.07% or 47±0.8 mmol/mol) and 14 (8 males; 6 females) glucose-tolerant controls matched for age, weight and body mass index (BMI). Muscle glycogen concentration increased by 17% after day-long eating in the control group (68.1±4.8 to 79.7±4.2 mmol/l; P=0.006), and this change inversely correlated with homoeostatic model assessment of insulin resistance [HOMA-IR] (r=−0.56; P=0.02). There was no change in muscle glycogen in the Type 2 diabetes group after day-long eating (68.3±2.6 to 67.1±2.0 mmol/mol; P=0.62). Liver glycogen rose similarly in normal control (325.9±25.0 to 388.1±30.3 mmol/l; P=0.005) and Type 2 diabetes groups (296.1±16.0 to 350.5±6.7 mmol/l; P<0.0001). In early Type 2 diabetes, the major physiological mechanism for skeletal muscle postprandial glycogen storage is completely inactive. This is directly related to insulin resistance, although liver glycogen storage is normal.

Rôles du sulfure d’hydrogène pour les muscles!

12/03/2015 | Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge

 

Role of hydrogen sulfide in skeletal muscle biology and metabolism
Sudhakar Veeranki                         Nitric Oxide Volume 46, 30 April 2015, Pages 66–71

• Tissue and species specific differences in endogenous H2S generators are present.
• H2S role in skeletal muscle biology and disease is not yet known.
• H2S might function in anaerobic ATP generation and mitochondrial protection.
• H2S role in metabolic diseases is controversial and needs further investigation.

Hydrogen sulfide (H2S) is a novel endogenous gaseous signal transducer (gasotransmitter). Its emerging role in multiple facets of inter- and intra-cellular signaling as a metabolic, inflammatory, neuro and vascular modulator has been increasingly realized. Although H2S is known for its effects as an anti-hypertensive, anti-inflammatory and anti-oxidant molecule, the relevance of these effects in skeletal muscle biology during health and during metabolic syndromes is unclear. H2S has been implicated in vascular relaxation and vessel tone enhancement, which might lead to mitigation of vascular complications caused by the metabolic syndromes. Metabolic complications may also lead to mitochondrial remodeling by interfering with fusion and fission, therefore, leading to mitochondrial mitophagy and skeletal muscle myopathy. Mitochondrial protection by H2S enhancing treatments may mitigate deterioration of muscle function during metabolic syndromes. In addition, H2S might upregulate uncoupling proteins and might also cause browning of white fat, resulting in suppression of imbalanced cytokine signaling caused by abnormal fat accumulation. Likewise, as a source for H+ ions, it has the potential to augment anaerobic ATP synthesis. However, there is a need for studies to test these putative H2S benefits in different patho-physiological scenarios before its full-fledged usage as a therapeutic molecule. The present review highlights current knowledge with regard to exogenous and endogenous H2S roles in skeletal muscle biology, metabolism, exercise physiology and related metabolic disorders, such as diabetes and obesity, and also provides future directions.

Le sulfure d’hydrogène (H2S) est traditionnellement reconnu comme gaz toxique possédant une odeur d’œufs pourris. Ce n’est qu’au cours des dernières décennies que le H2S s’est retrouvé parmi la famille des gasotransmetteurs avec l’oxyde nitrique et le monoxyde de carbone, et différents effets physiologiques du H2S ont été rapportés. Parmi les mécanismes moléculaires responsables des effets cellulaires les plus reconnus du H2S se trouvent la régulation de l’homéostasie intracellulaire redox et la modification post-traductionnelle des protéines par S-sulfhydration. D’un côté, le H2S peut promouvoir un effet antioxydant et est cytoprotecteur ; de l’autre, le H2S stimule le stress oxydant et est cytotoxique. Cet article de revue résume nos connaissances des effets antioxydants et prooxydants du H2S dans les cellules de mammifères et décrit les propriétés à deux côtés de ce nouveau gasotransmetteur. La régulation redox dans les effets cellulaires du H2S par l’intermédiaire de S-sulfhydration et le rôle du H2S ...

Plus tu manges sain, plus tu sera exposé aux pesticides!

12/03/2015 | Etudes Anti-âge

 

Cool
http://www.efsa.europa.eu/fr/efsajournal/pub/4037.htm

Page 1 sur 163 pages  1 2 3 >  Last »