Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free:

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site:, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Google Analytics

Targeted advertising cookies


The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at or by post at:

24, chemin de Borde Rouge –Auzeville – CS52627
31326 Castanet Tolosan CEDEX - France

Dernière mise à jour : Mai 2018

Menu Logo Principal logo Université Clermont Auvergne & associés

Human Nutrition Unit

Zone de texte éditable et éditée et rééditée

Christelle GUILLET, PhD


Email : contact
Tel : +33(0)4 73 60 82 58

Christelle Guillet

Many pathophysiological conditions (aging, obesity and other chronic diseases) are associated with muscle alterations. Depending on the circumstances, these impairments are related to both muscle mass and function and have for consequences a reduction in the mobility of people which can affect their quality of life and health. Thus, identification of factors responsible for these muscular alterations is necessary to define ways to maintain muscle mass and function in order to maintain the health and quality of life of elderly or patients with chronic diseases. Among the mechanisms involved in the loss of muscle mass and function, a postprandial anabolic resistance of muscle protein metabolism has been well demonstrated in old animals and elderly. This anabolic resistance is related in part to the development of insulin resistance frequently observed during aging. In a more general concept, insulin resistance seen in many clinical settings, could be seen as a contributor to muscle wasting.

Research Activities

Evolution of muscle mass and muscle protein metabolism in obesity: effect of exercise and lipid restriction.

The establishment of obesity in rats fed a high fat and high calorie diet is done in two phases: a dynamic phase of weight gain during the first 16 weeks of diet, during which muscle mass increases, then a phase static, from 16 to 24 weeks of diet, during which the weight stabilizes and muscle mass diminishes. During the weight gain phase, the muscle protein synthesis rate increases in glycolytic muscles. By contrast, during the weight stable phase, the rate of muscle protein synthesis decreases in these muscles. The changes observed in the glycolytic muscles during the static phase of obesity are associated with significant accumulation of intramuscular lipid. The second part of this study highlighted that after a period of obesity, practice an exercise in endurance combined with a fat balanced diet is associated with a significant weight loss if the exercise or diet are followed alone. Furthermore, this strategy also appears to be beneficial for the muscles because it improves muscle protein metabolism and changes induced by obesity.

The mass and quality of skeletal muscles are affected differently during the development of obesity and during the weight loss. Biochemical and molecular mechanisms involved in these changes remain to be demonstrated in order to identify effective nutritional or therapeutic strategies to limit the quantitative and qualitative loss of muscles especially during very restrictive diets and / or surgical treatment of obesity.


  • Guillet C, Masgrau A, Walrand S, Boirie Y. Impaired protein metabolism: interlinks between obesity, insulin resistance and inflammation. Obes Rev. 2012 Dec;13 Suppl 2:51-7.
  • Masgrau A, Mishellany-Dutour A, Murakami H, Beaufrère AM, Walrand S, Giraudet C, Migné C, Gerbaix M, Metz L, Courteix D, Guillet C, Boirie Y. Time-course changes of muscle protein synthesis associated with obesity-induced lipotoxicity. J Physiol. 2012 Oct 15;590(Pt 20):5199-210.
  • Guillet C, Delcourt I, Rance M, Giraudet C, Walrand S, Bedu M, Duche P, Boirie Y. Changes in basal and insulin and amino acid response of whole body and skeletal muscle proteins in obese men. 2009. J Clin Endocrinol Metab. 94(8):3044-50.
  • Guillet C, Zangarelli A, Gachon P, Morio B, Giraudet C, Rousset P, Boirie Y. Whole body protein breakdown is less inhibited by insulin, but still responsive to amino acid, in nondiabetic elderly subjects. 2004. J Clin Endocrinol Metab. 89(12):6017-24.
  • Guillet C, Prod'homme M, Balage M, Gachon P, Giraudet C, Morin L, Grizard J, Boirie Y. Impaired anabolic response of muscle protein synthesis is associated with S6K1 dysregulation in elderly humans. 2004. FASEB J. 18(13):1586-7.

Curriculum Vitae

2005-2006 : Post-doctorat : Karolinska Institute. Stockholm. Suède
2003-2005 : Attaché Temporaire d'Enseignement et de Recherche. Unité du Métabolisme Protéino-Energétique UMR 1019 INRA-Université d’Auvergne / Institut Universitaire de Technologie –Université d’Auvergne
2003 : Doctorat d'université en nutrition. Unité du Métabolisme Protéino-Energétique UMR 1019 INRA-Université d’Auvergne. Clermont-Ferrand
Activités d'enseignement :
UFR Médecine et Pharmacie, Université d'Auvergne, Clermont-Fd. Deuxième année du Diplôme de Formation Générale en Sciences Médicales (DFGSM2), 3 ème année de Licence Sciences, Technologies, Santé mention Sciences pour la santé parcours Nutrition, Master Sciences, Technologies, Santé mention Nutrition, Santé, Aliments, Diplôme Inter-Universitaire Nutrition et Activité Physique, Diplôme Universitaire Nutrition, Agression, Maladies Chroniques.
Activités de recherche :
Prix de recherche ESPEN (2015-2017 : responsable scientifique) : Impact of different protein levels intake on muscle mass and function in sarcopenic obese rats
Projet financé par la société Lactalis (2012-2014 : collaborateur scientifique) : Effet de la qualité des protéines alimentaires sur la fonctionnalité musculaire après une immobilisation chez le rat adulte et âgé.
Programme hospitalier de recherche clinique (2009-2012 : collaborateur scientifique) : Besoin protéique et intérêt des « protéines rapides » chez le sujet obèse opéré pour chirurgie bariatrique (BIBOP)
Projet financé par la Fondation Cœur et Artères (2008-2011 : partenaire) : Effet de l’activité physique et d’une diète sur le traitement du syndrome métabolique chez l’homme et chez le rat
Programme Hospitalier de Recherche Clinique (2007-2008 : collaborateur scientifique) : Impact de la stimulation cérébrale profonde du noyau sous-thalamique sur la production hépatique de glucose dans la maladie de Parkinson.