Aims

To support the free and open dissemination of research findings and information on alcoholism and alcohol-related problems. To encourage open access to peer-reviewed articles free for all to view.

For full versions of posted research articles readers are encouraged to email requests for "electronic reprints" (text file, PDF files, FAX copies) to the corresponding or lead author, who is highlighted in the posting.

___________________________________________

Thursday, June 30, 2011

Resveratrol prevents the wasting disorders of mechanical unloading by acting as a physical


Long-term spaceflight induces hypokinesia and hypodynamia, which, along microgravity per se, result in a number of significant physiological alterations, such as muscle atrophy, force reduction, insulin resistance, substrate use shift from fats to carbohydrates, and bone loss. Each of these adaptations could turn to serious health deterioration during the long-term spaceflight needed for planetary exploration.

We hypothesized that resveratrol (RES), a natural polyphenol, could be used as a nutritional countermeasure to prevent muscle metabolic and bone adaptations to 15 d of rat hindlimb unloading. RES treatment maintained a net protein balance, soleus muscle mass, and soleus muscle maximal force contraction.

RES also fully maintained soleus mitochondrial capacity to oxidize palmitoyl-carnitine and reversed the decrease of the glutathione
vs. glutathione disulfide ratio, a biomarker of oxidative stress. At the molecular level, the protein content of Sirt-1 and COXIV in soleus muscle was also preserved.

RES further protected whole-body insulin sensitivity and lipid trafficking and oxidation, and this was likely associated with the maintained expression of FAT/CD36, CPT-1, and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) in muscle.

Finally, chronic RES supplementation maintained the bone mineral density and strength of the femur.

For the first time, we report a simple countermeasure that prevents the deleterious adaptations of the major physiological functions affected by mechanical unloading.

RES could thus be envisaged as a nutritional countermeasure for spaceflight but remains to be tested in humans.




Read Full Abstract

Request Reprint E-Mail: stephane.blanc@iphc.cnrs.fr