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: https://www.ghostery.com/fr/products/

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: http://www.youronlinechoices.com/fr/controler-ses-cookies/, 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

Realytics
Google Analytics
Spoteffects
Optimizely

Targeted advertising cookies

DoubleClick
Mediarithmics

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 cil-dpo@inra.fr or by post at:

INRA
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

Dr Isabelle SAVARY-AUZELOUX

.

Dr Isabelle SAVARY-AUZELOUX 

AUZELOUX_SAVARY-Isabelle

Email : contact
Tel : +33(0)4 73 62 47 32

  Research Activities       Publications       Curriculum vitae

Demographic changes in our countries are characterized by a progressive ageing of the populations. One of the major features of ageing is sarcopenia consisting in an unintentional and physiological loss of muscle mass and strength. Sarcopenia targets all ageing individuals, including persons presenting a good health status but prevails in frail population. It is a one of the major factor leading to incapacity and morbidity in the aged population. Sarcopenia is a physiological impairment due to various causes: malnutrition, lower physical activity, low grade inflammation, oxidative stress, obesity and gradual installation of an insulin-resistant state (IR).

My research program consists in the understanding of the early events leading to the installation of metabolic perturbations and the IR state both in healthy individuals fed an obesogenic diet but also in the elderly population. I focus my research on adaptive mechanisms developed by the body during IR installation and the impact of these mechanisms on nutrients (energy, nitrogen …) metabolism in insulin or nutrients-targeted tissues and organs (i.e. liver, gut and in fine muscle/adipose). More recent developments of my research area include the role of the gut microbiota in the development of IR and ageing-related metabolic perturbation, its interaction with the diet components and the synthesis of key metabolites (such as short chain fatty acids and other metabolites investigated by “omics” strategies) involved in the dialog between the host and its microbiota in these pre-pathological situations.Nutritional strategies, targeting gut microbiota, and capable to limit or delay the development of IR and age-related metabolic perturbations are also studied, particularly the role of dietary fermentable fibers and probiotics.

Activités de recherche

 Research Activities       Publications       Curriculum vitae

Integrative approaches are used and allow the investigation of interactions between tissues and organs for metabolisms regulation and nutrients bioavailability (gut/microbiota/liver/muscle, specific requirements and metabolisms or specific organs). We also investigate the impact of dietary components (proteins/energy substrates/dietary fibers/probiotics) on metabolic regulations at whole body and tissue level both qualitatively and quantitatively (bioavailability, net nutrients fluxes at tissue level, signals…)

These concepts are tested in human volunteers, rodents (including old rats), and an original model of mini-pigs multicatheterized at the digestive/hepatic or muscle levels. These different models allow an integrative and dynamic approach of metabolic fluxes of nutrients both at the whole body and tissue/cellular levels using labeled molecules, classical biochemical approach, metabolomics (plasma, urine, fecal water) and proteomics (at hepatic and muscle levels).

Key results:

Time events concurring to IR development in mini pigs : Ageing is characterized by a lower muscle response to the meal anabolic signal (particularly leucine). To this muscle-targeted mechanisms can be also associated alterations of metabolic cross-talks between tissues from the splanchnic area (gut and liver, including microbiota within the gut) and muscle for nutrients use. In a model of gut and liver catheterized mini-pig, we have shown that metabolic adaptations were occurring very early following the ingestion of an obesogenic diet (within the first 15 days) and that the liver and gut were adapting very quickly their energy metabolism to deal with the dietary overflow of nutrients (decreased glucose net uptake, increased lactate net production, rapid alteration of catabolism of branched chain amino acids).

Prebiotics : fermentable fibers. We have performed an integrated and comprehensive study of the interaction diet/microbiota/gut/produced metabolites from microbiota (from dietary fibers fermentation) or dietary origin on the bioavailability of nutrients to the peripheral tissues such as muscle (and kinetics of IR development). We have shown that a mix of fermentable dietary fiber was capable to reverse some of the adverse effects of a 2 months adaptation to an obesogenic diet in mini pigs: limitation of lipids droplets accumulation in the liver (via a decreased lipogenic activity and lipids entry in the hepatocytes) and increased oxidative capacity and mitochondrial activity in the muscle to catabolize the excess of lipids present in the diet. These latter data were obtained combining multicatheterized minipigs, “classical” biochemistry and molecular biology as well as “omics” methodologies: proteomics, metabolomics in the host and metagenomics of gut microbiota.

Probiotics : impact on the gut to target the muscle. We have shown, in old rats subjected to gut inflammation (induced by Sodium Dextran Sulfate, DSS), that a probiotic strain (Streptococcus Thermophilus) was capable to limit the DSS induced-hypermetabolism (and stimulation of protein synthesis) in the gut. This led to an increased availability of amino acids at the muscle level, a sustained protein synthesis and lower muscle loss in DSS-probiotic supplemented animals compared to DSS alone. The strain has been patented and underlying mechanisms of action under investigation.

Dr Isabelle SAVARY-AUZELOUX Publications

Publications
Read more

Dr Isabelle SAVARY-AUZELOUX

.
Read more